C

cabanne A primitive one-room dwelling used by the early French pioneers in the Mississippi Valley as a temporary shelter; had a framework consisting of poles with branches woven between them; a steeply pitched gable roof, thatched with palmetto fronds or bark attached to a wood framework; somewhat similar to the palma hut in Florida.

cabin A simple one-story cottage or hut, often of relatively crude construction; see center-hall cabin, continental cabin, dog-run cabin, dogtrot cabin, double-pen cabin, log cabin, possumtrot cabin, saddlebag cabin, single-pen cabin, stone cabin, tourist cabin, vertical log cabin, Virginia cabin.

cabin court A motel, usually consisting of individual cabins.

cabinet 1. A private room for study or conference. 2. A suite of rooms for exhibiting scientific and artistic curiosities. 3. A case or box-like assembly consisting of shelves, doors, and drawers and primarily used for storage. 4. An enclosure having a front hinged door or doors, for housing of electrical devices or conductor connections. 5. In French Vernacular architecture of Louisiana, one of two areas at the rear corners of a typical house; one was used for sleeping or storage, and the other used to house a stairwell.

cabinet conditioner See room air conditioner.

cabinet drawer kicker See drawer kicker.

cabinet drawer runner See drawer runner.

cabinet drawer stop See drawer stop.

cabinet file A single-cut file, half-round on one side, flat on the other.

cabinet filler A wood member which closes the space between cabinets and adjacent walls or ceilings.

cabinet finish A varnished or polished hardwood interior finish as distinguished from a painted softwood finish.

cabinet heater A heater containing a heating element enclosed in a metal cabinet, usually with an intake grille below, and an outlet for the heated air above; often contains a fan.

cabinet jamb A steel doorframe in three or more pieces applied as the finished frame over a rough buck.

cabinet lock A spring bolt.

cabinet scraper A flat steel blade used for smoothing a wood surface after it has been planed, or for scraping paint, etc., from the surface.

cabinet window A type of projecting window or bay window for the display of goods in shops; much used early in the 19th cent.

cabinet work Built-in cabinets and shelves, often of fine quality, as in joinery.

cable 1. An electric conductor consisting of a group of smaller-diameter conductor strands twisted together. 2. A group of electric conductors which are insulated from each other. 3. Any heavy rope or wire line used for support, for exerting a force, or for controlling a mechanism. 4. One of the reedings which are set into the flutes of a pilaster or column.

cable bond An electrical connection (a) between the armor or sheath of one cable and that of an adjacent cable, (b) across a joint in the armor or sheath of a cable, or (c) between the armor or sheath and the earth.

cable conduit See conduit, 1. Also see cable duct.

cabled fluting, ribbed fluting, stopped flute A molding of convex section formed in the flutes of a column, usually in the lower third of the shaft.

cable duct A rigid metal duct through which insulated electric conductors are run, generally conductors carrying large currents; for underground installations, concrete pipes usually are used.

cable grip A device temporarily connected to the end of a cable to assist in pulling the cable during its installation.

cable jacket The protective covering over the core, insulation, or sheath of a cable.

cable molding See cabling.

cable pulling compound A substance which facilitates the pulling of wires through a cable duct or conduit.

cable rack Same as ladder cable tray.

cable roof A structural system consisting of a roof-deck and covering which are supported by cables.

cable sheath A single layer or multiple layers of a protective covering over a cable.

cable support box In an installation of electric conduit that runs vertically, a box which provides support for the cables within the conduit so as to limit the strain on them from their own weight.

cable-supported construction A structure that is held in equilibrium by cables.

cable tray An assembly of metalwork which is used to support insulated electric conductors; similar in function to a metal cable duct, but consisting of a ladder-like metal framework on the bottom and sides, with the top open.

cable vault An underground structure used in pulling or splicing electric cables which are laid underground.

cableway An apparatus for moving material, sometimes used at construction sites; usually a wire rope which is suspended between two points, from which buckets, or the like, are hung and pulled along.

cabling, cable molding 1. An ornament formed like a cable, showing twisted strands. 2. The convex filling of the lower part of the flutes of classical columns. Also see rope molding, reeding.

Cabot’s quilt An insulating material consisting of dried eelgrass held between layers of cloth or paper; once used as thermal insulation, now little used.

CAB plastic See cellulose acetate butyrate plastic.

cab-tire cable A flexible cable having a heavy rubber or neoprene outer sheathing.

CAD Abbr. for computer-aided design.

cadaster A public record or survey of the value, extent, and ownership of land that serves as a basis for taxation.

cadastral survey A survey relating to land boundaries and subdivisions, made to create units suitable for transfer or to define the limitations of title.

cadmium plating An electroplating which provides a corrosion-resistant coating on metal.

cadmium yellow A strong yellow pigment, cadmium sulfide, characterized by good permanence; used in paints.

caementicius In ancient Rome, irregular masonry built of rough quarry stones not squared or shaped in any way.

caementum Ancient Roman masonry formed of small rough stones set in a mixture of concrete.

Caen stone A stone from Caen (in Normandy) used in some medieval buildings in England.

caer- A prefix signifying a fortified wall, castle, or city, occurring in place names in Wales and parts of western and northern England.

caernarvon arch Same as shouldered arch.

cage 1. Any rigid, reinforced assembly, ready for placing in position. 2. A metal enclosure for balcony spotlights. 3. A chantry or chapel screened by open tracery.

caged beam A beam enclosed in a casing, 2, usually by a fire-rated construction.

caged column A column enclosed in a casing, 2, usually by a fire-rated material; also see column casing.

cage of reinforcement A system of concrete reinforcement bars; see illustration under reinforcing rods.

caher In Ireland, ancient stonework thought to have been intended for defensive work for a church or for several sacred buildings.

cairn A pile of stones heaped up for a landmark, memorial, or monument; a tumulus.

caisson 1. A watertight structure or chamber, within which work is carried on in building foundations or structures below water level. 2. A sunken panel, esp. in a vaulted ceiling or the inside of a cupola; a coffer.

caisson drill An auger-like machine (or an attachment for a crane) used in foundation work to cut a vertical or inclined circular shaft in the earth for a building footing which is carried to solid material beneath.

caisson pile A cast-in-place pile; made by driving a tube into the ground, emptying the tube, then filling with concrete.

Cajun cottage, Cajun cabin A simple dwelling built by immigrants (Acadians) from the Maritime Provinces of Canada who, from about 1760 to 1790, settled largely in the bayou districts of southern Louisiana where their descendants are now usually referred to as Cajuns. In the early 1800s, the typical Cajun cottage was built on groundsills, supported on cypress blocks or brick piers; usually characterized by a shingle-covered, moderately steep end-gabled roof; hand-riven clapboard siding; rooms positioned in a relatively straight line from the front to the back of the house; French doors at the front and rear to promote the flow of air through the house; a porch across the front, commonly without a railing; usually a steep stairway from one end of the porch to a loft above; battened doors; battened shutters on the windows.

caking In paints, the formation of a hard dense mass of pigment which is difficult to disperse by hand agitation.

CAL On drawings, abbr. for “calorie.”

calathus The basket-shaped or bell-shaped core of a capital, esp. Corinthian.

calcareous Containing calcium carbonate or, less generally, containing the element calcium.

calcimine, kalsomine A low-cost wash coating consisting of glue and whiting (usually powdered calcium carbonate) mixed with water, sometimes tinted; used on plaster or masonry-type surfaces.

calcine To heat a substance below the temperature of fusion to drive off chemically combined water or to alter its chemical and physical characteristics.

calcined gypsum A gypsum that has been partially dehydrated by heating.

calcite A mineral form of calcium carbonate; the principal constituent of limestone, chalk, and marble; usually a major raw material used in portland cement manufacture.

calcite streak A former fracture or parting (in limestone) that has been recemented and annealed by deposition of calcite.

calcium aluminate cement, aluminous cement, (Brit.) high-alumina cement The product obtained by pulverizing clinker, consisting essentially of hydraulic calcium aluminates resulting from fusing or sintering a suitably proportioned mixture of aluminous and calcareous materials.

calcium carbonate A low-density white pigment for use in paint; provides little opacity; used mainly to provide bulk and flatness.

calcium chloride A chemical salt used in plastic concrete as an accelerator.

calcium hydroxide Same as hydrated lime, 2.

calcium oxide See lime.

calcium silicate brick Same as sand-lime brick.

calcium silicate insulation Hydrated calcium silicate with inorganic fiber reinforcement, molded into rigid shapes.

calcium stearate A product of the reaction of lime and stearic acid; used as an integral water repellant in concrete.

calcium sulfate Anhydrite or gypsum dihydrate which has been calcined to the point at which all the water of crystallization has been removed.

calcium sulfate cement A cement that depends primarily on the hydration of calcium sulfate for its setting and hardening properties; includes Keene’s cement, Parian cement, plaster of paris.

calcium sulfate hemihydrate Gypsum which has been calcined to the point at which 75% of the water of crystallization has been removed.

calculated live load 1. The live load which is specified by the applicable building code. 2. The actual load applied in service.

calculon A brick 21.9 cm long, 17.8 cm wide, and 6.6 cm high.

caldarium The hot plunge in a Roman bath.

calefactory A heated common room in a monastery.

calendar A sculptured or painted emblematic series of the months.

calfdozer A small bulldozer.

calf’s-tongue molding, calves’-tongue molding A molding consisting of a series of pointed tongue-shaped elements all pointing in the same direction or toward a common center when around an arch.

calfiz In Hispanic architecture, a rectangular ornamental frame around a door.

calfret An early term for caulk.

caliber The nominal internal diameter of a pipe. In contrast, the outside diameter is specified for brass and copper tubing and for brass and copper pipe of other than iron-pipe sizes.

calibre Same as caliber.

caliche Gravel, sand, or desert debris cemented by porous calcium carbonate or other salts.

caliduct 1. A duct or pipe for conveying hot air, hot water, or steam for heating. 2. In the ancient Roman systems of furnace heating, a hot-air flue, usually of terra-cotta or built up with brick partitions and tile facings.

California bearing ratio A ratio used in determining the bearing capacity of a foundation; defined as the ratio of the force per unit area required to penetrate a soil mass with a 3 sq in. (19.4 sq cm) circular piston at the rate of 0.05 in. (1.27 mm) per min to the force required for corresponding penetration of a standard crushed-rock base material; usually determined at a penetration of 0.1 in. (2.54 mm).

California bungalow, California Craftsman A loosely used term applied to a small one-story or one-and-a-half-story wood bungalow, often in the Craftsman style; widely found in California from about 1890 to 1920 as well as in other areas of the United States.

California ranch house See ranch house.

caliper An instrument, resembling a pair of dividers, with adjustable legs for measuring the diameter or the thickness of bodies. Also see inside caliper and outside caliper.

caliper stage In a theater, a stage having side arms, which may be used for acting, on both sides of the main stage or apron.

calking Same as caulking.

calliper Same as caliper.

call box See fire alarm box.

call loan A loan that is payable at any time on the demand of the lender; in some instances, the borrower may also have the right to repay the loan at any time he chooses.

call for bids A formal request for bids for work to be performed on a building project.

call point See fire-alarm box.

calme See came.

calorie The heat required to raise the temperature of 1 gram of water 1°C; now called a small calorie. A large calorie is equal to 1000 small calories, i.e. a kilocalorie.

calorific value The amount of heat liberated by the combustion of a unit weight (or if a gas, a unit volume) of fuel.

calorifier (Brit.) A storage vessel, not open to the atmosphere, in which a supply of water is heated.

calotte A dome, cupola, or structure of similar form, as a cup-shaped ceiling, the head of an alcove, etc.

calves’-tongue molding See calf’s-tongue molding.

calyon Flint or pebble-stone; used in building walls, etc.

calyx An ornament resembling the outer protective covering of a flower; found, for example, in the Corinthian capital.

cam In a lock, a rotating piece attached to the end of the cylinder plug to engage the locking mechanism.

CAM On drawings, abbr. for camber.

camara Same as camera.

camarn In a church, a camera, 3 used for storing images, adornments, and the like.

camber 1. A slight convex curvature built into a truss or beam to compensate for any anticipated deflection so that it will have no sag when under load. Also see bow. 2. A slight convex curvature of any surface, e.g., to facilitate the runoff of water.

camber arch An arch having little rise; essentially a flat arch having a slightly upward curve toward its midpoint.

camber beam A beam curved slightly upward toward the center.

camber board A template which performs the same function as a camber diagram.

camber diagram A diagram, used in construction, which indicates the specified camber at all points along the length of a truss or beam.

camber piece, camber slip A slightly curved wood board used as a support in laying a brick arch having a small rise.

camber window A window arched at the top.

cambium The cellular layer of wood tissue between the bark and sapwood of a tree.

cambogé A concrete masonry unit with transverse openings; used in tropical architecture, often decoratively, to permit ventilation while excluding sunlight, as in a brise-soleil.

came A slender rod of cast lead, with or without grooves, used in casements and stained-glass windows, to hold together the panes or pieces of glass.

camelback truss A truss having a broken outline for the upper chord, composed of a series of straight segments, taking the humped shape of a camel’s back.

camelhair mop A soft-haired brush which is used for varnishing, gilding, and filling in narrow spaces.

camera 1. In ancient architecture, an arched roof, ceiling, or covering; a vault. 2. A room having an arched ceiling; a vaulted room. 3. A small room, small hall, or chamber.

camerated Having an arched or vaulted appearance.

camera vitrea A vaulted ceiling, having its surface lined with plates of glass.

cam handle, locking handle In a window having a sash (ventilator, 2) which swings about pivots, a handle which locks the sash in a closed position by wedging it against a keeper.

campana The body of a Corinthian capital.

campanario In Mission architecture, a belfry or a pierced wall that serves as a belfry, with a bell usually hung in an arched opening.

campaniform Bell-shaped.

campanile A bell tower, usually freestanding.

campanulated Bell-shaped.

camp ceiling 1. A ceiling shaped like the interior of a truncated pyramid. 2. The ceiling within the roof of a building, the sides of which are sloped, following the line of the rafters, but the center of which is flat. 4. A ceiling that sags inwardly like a tent. Also called a camp ceiling or tent ceiling.

camp sheeting Sheetpiling used for foundation work in sandy soil.

campus The grounds and buildings of a university, college, or school.

can Abbr. for canvas.

Canadian Standards Association In Canada, a membership organization serving industry, educational institutions, and government in the field of standardization, including the standardization of building components, materials, and testing. Also see Construction Specifications Institute Canada.

canal, canalis A channel or groove, as a hollow between the fillets of the volutes of an Ionic capital.

canale In Spanish Colonial architecture, a waterspout used to drain rainwater from an essentially flat roof; it projects through, and beyond, the face of the parapet around the roof.

canaliculus A small channel or groove, as a fluting carved on the face of a triglyph.

canary whitewood Same as tulipwood, 1.

canary wood See balaustre.

cancela In Spanish architecture and its derivatives, a large gate often of ironwork or a massive wood gate, usually decorated with spindlework or a lattice grille.

cancelli Barred screens in a basilica, separating the clergy from the laity, in Early Christian architecture.

candela The International Standard unit of luminous intensity; closely approximates the formerly accepted unit known as the “international candle.”

candelabrum 1. A movable candle lampstand with central shaft and, often, branches or a decorative representation thereof. 2. A lighting device designed as an architectural fixture, composed as in definition 1, above. Also see lamppost.

candela per unit area See luminance.

candle beam In old churches, a horizontal beam, bar, or rail furnished with prickets for holding candles, each of which has a saucer or tray to catch the drippings; placed over or near the altar, and also at the entrance to the choir or chancel, where the rood beam or rood screen was placed in richer churches.

candlepower (cp) The luminous intensity of a light source, expressed in candelas. Abbr. cp. Also see apparent candlepower.

candle-snuffer roof Same as conical roof.

cane bolt A heavy cane-shaped bolt with the top bent at right angles; installed at the bottom of a door.

cane fiberboard A fiberboard primarily composed of sugar-cane fibers after juice has been extracted from the cane (bagasse); held together by a binder.

canephora, canephorus 1. Ornament representing a maiden (youth) bearing a basket of ceremonial offerings on the head. 2. A caryatid with basket on her head; used either as a support or as a freestanding garden ornament.

cannelated Said of a surface that is fluted or grooved.

caño A water conduit, pipe, or clay-tile spout on a Hispanic building.

canonnière A hole left in a retaining wall to permit water in the earth behind the wall to drain through it.

canopy 1. A decorative hood above a niche, pulpit, choir stall, or the like. 2. A covered area which extends from the wall of a building, protecting an entrance or loading dock. 3. The collective term for the upper blanket of foliage on trees.

canopy of honor Same as celure.

canopy roof A roof, often over a balcony or porch, that is suggestive of the curvature of a suspended cloth canopy.

cant 1. A salient corner. 2. A line or surface angled in relation to another, as a sloped wall. 3. Masonry “on cant” is laid with joints sloping between front and back surfaces; the vertical joints are laid normally. 4. A log partly or wholly squared off.

cant bay A bay erected on a plan of canted outline.

cant-bay window A cant window.

cant beam A beam having its edges beveled or chamfered.

cant board A board which is laid so as to cant a surface, as under the first row of shingles on a roof, or to support lead sheeting on each side of a valley gutter; a cant strip.

cant brick See splay brick.

canted Having a cant, 2; said of a wall, etc.

canted coursing Moderately-pitched courses of brick or masonry in a vault.

canted molding A wood raking molding.

canted wall A cant wall.

cantharus A fountain or basin in the atrium or courtyard before ancient and some Oriental churches, where persons could wash before entering the church.

cantherius A principal rafter in an ancient wooden roof.

cantilever 1. A beam, girder, truss, or structural member or surface that projects horizontally beyond its vertical support, such as a wall or column. 2. A projecting bracket used for carrying the cornice or extended eaves of a building.

cantilever arch An arch that is supported by flat projections on opposing walls.

cantilever barn A barn having its second floor projecting beyond the structure of the ground floor; especially found in the southern regions of the US.

cantilever beam A beam which is supported only at one end.

cantilevered window Same as oriel.

cantilever footing A footing having a tie beam to another footing to balance a structural load not symmetrically located with respect to the footing.

cantilever form Same as slip form.

cantilever retaining wall See cantilever wall.

cantilever steps Steps built into the wall at one end, but supported at the other end only by the steps below.

cantilever truss A truss overhanging its support at one end and anchored at the other.

cantilever wall A reinforced concrete wall which resists overturning by the use of cantilever footings.

canting strip A water table, 1.

cant molding A square or rectangular molding with the outside face beveled.

canton A corner of a building decorated with a projecting masonry course, a pilaster, or similar feature.

cantoned Ornamented at the corners with projecting pilasters.

cantoned pier Same as pilier cantoné.

cantoria A church choir gallery.

cantoris Of (or belonging to) the cantor or pre-cantor, for example—the cantoris side of the choir in a church; the left or north side as one faces the altar.

cant strip 1. A beveled strip of wood or other material used esp. under built-up roofing where the roofing turns up, providing a gradual transition; used to prevent the cracking of roofing applied over it; as arris fillet. 2. A tilting fillet; a doubling piece. 3. A cant board.

cant wall A wall canted on plan.

cant window, cant-bay window A bay window erected on a plan of canted outline; the sides of the window are at an angle with respect to the wall; also see angled bay window.

CANV On drawings, abbr. for canvas.

canvas A closely woven cloth of cotton, hemp, or flax; sometimes adhered to a wall or deck to serve as a substrate for paint; used to cover roof decks that are walking surfaces or sun decks.

canvas wall A plastered wall to which a layer of canvas has been applied to serve as a base for wallpaper.

cap 1. Usually, the topmost member of any vertical architectural element, often projecting, with a drip as protection from the weather, e.g., the coping of a wall, top of a pedestal or buttress, the lintel of a door, etc. 2. A layer of concrete placed over rock in the bottom of foundation excavations to level the exposed surface, prevent its deterioration by weathering, and protect it from other damage. 3. The upper member of a column, pilaster, door cornice, molding, and the like; also called cap trim, wainscot cap, dado cap, chair rail cap, capital. 4. A fitting used to close the top end of a tubular newel. 5. A blasting cap. 6. A fitting used to close the end of a pipe. 7. A plane surface which is bonded to the bearing surface of a test specimen during its strength testing to ensure a uniform load distribution.

capacitance The quantitative measure of the electric-energy storage capability of a capacitor; usually measured in farads or microfarads (10⁻⁶ farads).

capacitance alarm A device which is electrically connected to a protected metal enclosure (such as a safe, vault, file, or security cabinet) so that the enclosure itself becomes part of a balanced-capacitance circuit. A person approaching the protected cabinet unbalances the electrical circuit and activates a security alarm.

capacitor An electric component which consists of conducting plates insulated from each other by a layer of dielectric material; introduces capacitance into a circuit.

capacitor motor A single-phase induction motor with its main winding connected to a source of power and having an auxiliary winding connected in series with a capacitor to facilitate starting.

capacity 1. See carrying capacity. 2. The volume contained in a vessel. 3. The maximum or minimum water flow obtainable under given conditions (e.g., specified conditions of pressure, temperature, and velocity).

capacity insulation The ability of masonry to store heat; depends on its mass, density, and specific heat.

cap block Same as drive cap.

cap cable In prestressed concrete, a short cable introduced to prestress the zone of negative bending.

Cape Ann house A rectangular house, commonly one or one and a half stories high, that is similar to a Cape Cod house, but has a shingled mansard roof rather than a shingled gable roof.

cape chisel A long cold chisel which has a long taper and a narrow cutting edge; used for cutting keyways and the like.

Cape Cod house A colonial one-and-a-half-story rectangular house of wood-frame construction that originated on Cape Cod, Massachusetts. Usually characterized by: a massive central chimney serving all fireplaces; a gable roof; a roof covering and exterior wall covering of hand-split wood shingles, left unpainted to weather to a gray color; double-hung windows on the first story and often on the gable-end walls; paneled doors; a partial basement. Cape Cod houses are of three types: full Cape house, which has two windows on each side of the front door; three-quarter Cape house, which has two windows on one side of the front door and a single window on the other side; and a half Cape house, which has two windows on one side of the front door and none on the other.

Cape house A term used in some parts of New England for a Cape Cod house.

cap flashing Same as counterflashing.

capellaccio A local tufa stone used for building construction in ancient Rome.

cap house A small enclosure, at the top of stairs in a turret or tower, which leads to the parapet around a roof.

capilla abierta A Hispanic open chapel, usually adjacent to a church.

capilla major 1. The principal chapel in Spanish churches. 2. The area directly around the high altar of a church.

capillary action, capillarity 1. The movement of a liquid in the interstices of soil or other porous material, as a result of surface tension. 2. The phenomenon responsible for dry soil sucking up moisture above the ground water level. Also see capillary flow.

capillary break A space between two surfaces which is purposely made wide enough to prevent the movement of moisture through the space by capillary action.

capillary flow The flow of moisture through a capillary pore system, as in concrete.

capillary groove A groove formed between two building components to prevent capillary action between them.

capillary joint Same as sweat joint.

capillary migration See capillary flow.

capillary space In cement paste, any space not occupied by anhydrous cement or cement gel. Air bubbles, whether entrained or entrapped, are not considered to be part of the cement paste.

capillary tube A tube of small internal diameter; used in refrigeration as a control for the flow of liquid refrigerant, or as an expansion device between the condenser and evaporator; or used to transmit pressure from the sensitive bulb of a temperature control to the operating element.

capillary water Water, above the water table, held there by capillary action.

capital The topmost structural member of a column, pilaster, anta, or the like, often decorated; may support an architrave, 1 or may be surmounted by an impost. See illustrations under the various orders; also see angle capital, basket capital, bracket capital, bud capital, Byzantine capital (illustrated under Byzantine architecture), Composite capital, Corinthian capital, corner capital, cushion capital, Doric capital, Hathoric capital, protomaic capital, Ionic capital, lotus capital, palm capital, scalloped capital, water-leaf capital.

capital cost The cost of acquiring a building, including any substantial improvements the building may require.

capital messuage The main dwelling of a manor house. See messuage.

capitol Official meeting place for a legislative body.

cap molding, cap trim 1. Molding or trim which embellishes the top of a dado. 2. Molding, at the head of a window or door, above the simple trim of the casing.

cappella del coro The choir, or chapel of the choir.

capping Any architectural member serving as a cap, 1, such as a coping.

capping brick Same as coping brick.

capping in The application of roofing felt to a roof-deck.

capping piece, cap piece, cap plate A piece of timber covering the heads of a series of uprights or other vertical structure.

capping plane A plane used for rounding the upper surface of wooden railings.

cap plate 1. A capping piece. 2. The top plate on a steel column or post; usually supports a load.

cap rail A rail, 1 fastened to the uppermost member of a railing system.

capreolus In an ancient timber roof, a brace or strut; a king post or tie beam.

cap screw 1. A screw which is threaded along its entire length and has a chamfered point; it is driven into a hole and secured without a nut. 2. Same as tap bolt.

cap sheet A coated felt, usually mineral-surfaced; used as the top ply of a built-up roofing membrane. See asphalt prepared roofing.

cap tile A tile used as a coping stone atop a wall.

capstone 1. Any single stone in a coping. 2. A stone placed at the top of a stone arch.

captain’s house In colonial New England, a house having a truncated hipped roof and chimneys at both gable ends; has a widow’s walk and/or a cupola on the roof.

captain’s walk See widow’s walk.

cap trim See cap molding.

car See elevator car.

caracole A spiral stair.

car annunciator An electric device in an elevator car which provides a visual indication of floor landings.

carapa, crabwood, Surinam mahogany, West Indian mahogany A pale to reddish brown wood of South America and Africa; moderately hard and heavy, with straight grain and medium texture; used for general construction and in plywood.

caravansary, caravanserai 1. In the middle east, a building or inn for the overnight lodging of travelers by caravan; usually enclosed by a solid wall and entered through a large gate. 2. By extension, any large inn or hotel.

carbonaceous Said of rock containing organic matter.

carbon-arc cutting An arc-cutting process in which the severing of metal is effected by melting with the heat of an arc produced between the carbon electrode and the metal being cut.

carbon-arc lamp A high-intensity electric-discharge lamp employing an arc discharge between carbon electrodes.

carbon-arc spotlight A spotlight employing a high-intensity arc light source.

carbon-arc welding An arc-welding process wherein coalescence is produced by heating with an arc between a carbon electrode and the work.

carbonation The reaction between carbon dioxide and calcium compounds, esp. in cement paste, mortar, or concrete, to produce calcium carbonate.

carbon black A synthetically produced black pigment, almost pure carbon; used to color paint and concrete because of its high shading strength. Also see animal black.

carbon dioxide extinguishing system A fire-extinguishing system in which the extinguishing agent is carbon dioxide supplied from a pressurized vessel through fixed pipes and nozzles; includes an automatic fire detection system and an actuating mechanism.

carbon steel 1. Steel having no specified minimum content of alloying elements. 2. Steel having a specified minimum copper content not exceeding 0.40%. 3. Steel having a maximum specified content as follows: manganese 1.65%, silicon 0.60%, copper 0.60%.

carcase Same as carcass.

carcass, carcase 1. The framework of a building before the addition of sheathing or other covering. 2. The frame or main parts of a structure unfinished and unornamented, lacking masonry, brickwork, floors, carpentry, plastering, inside trim, etc.

carcass flooring The frame of timbers which supports the floorboards above and the ceiling below.

carcass roofing A framework of timber which spans a building and carries the boarding and other covering.

carcer 1. A prison. 2. A starting stall in a Roman circus for horse or chariot races. 3. The dens for beasts in an amphitheater.

card frame, card plate A metal frame, attached to a door or drawer, which holds a name card or label.

cardo A hinge or pivot, used in ancient construction to hang a door.

car door See elevator car door.

car door contact, gate contact An electric device which prevents movement of an elevator car unless its door (or gate) is in the closed position.

care, custody, and control Describes a standard exclusion in liability insurance policies. Under this exclusion, the liability insurance does not apply to damage to property in the care or custody of the insured, or to damage to property over which the insured is for any purpose exercising physical control.

car-frame sling Same as elevator car-frame sling.

carillon 1. A bell tower; a campanile. 2. A set of fixed bells, usually hung in a tower and struck by hammers.

carnarvon arch A lintel supported on corbels.

carnauba wax A hard, high-melting-point wax; used in wood polishes and coatings to produce a matte finish.

carnel, crenelle Same as the embrasure of a battlement.

carnificina In ancient Rome, a subterranean dungeon in which criminals were tortured and in many cases executed.

carol An area in a cloister set off by screens, partitions, or railings; similar in use to a carrel.

Carolean Said of the periods of the reigns of King Charles I (1625–1649) and Charles II (1660–1685) of England; also called Caroline.

Carolingian architecture The pre-Romanesque architecture of the late 8th and 9th cent. in France and Germany, based on Roman forms. So called after the emperor Charlemagne (768–814). The cathedral of Aachen is the best-known example.

carolytic, carolitic Descriptive of a column having a foliated shaft.

carousel packer An automatic refuse compactor in which compacted waste materials are compacted and packaged in bags arrayed along a circular carriage; designed for high-volume and/or for long, unattended operation.

car park (Brit.) A parking lot.

Carpenter Gothic, Carpenter Gothic Revival A mid-19th century architectural style in which highly decorative woodwork and Gothic motifs were applied to otherwise simple homes or churches in America, usually designed and constructed by carpenters and builders; often asymmetric in plan. Buildings in this style are often characterized by: a façade that promotes vertical emphasis, such as by pointed arches that extend into the gables; Gothic motifs such as foliated ornaments, pinnacles with battlements, crockets, decorative brackets, foils, towers, turrets, and wall dormers suggestive of Gothic architecture; often, an entry porch having a flattened Gothic or Tudor arch; a steeply pitched roof or gabled roof, often with a gable at the center of the façade or with intersecting gables; lacy, highly ornate bargeboards and finials decorating the gables and dormers; decorative shingle patterns on the roof; high, ornamental chimney stacks; often, clusters of chimney pots; bay windows, casement windows with diamond-shaped or rectangular-shaped panes, lancet windows, ogee-arch windows, oriel windows, stained-glass windows, triangular arch windows often with mullions and relatively thin tracery; label moldings; often elaborately paneled entry doors in a Gothic motif; a wood-paneled door or a battened door suggestive of the medieval period, sometimes bordered with sidelights. Occasionally called Carpenter’s Gothic.

carpenter’s brace Same as brace, 3.

carpenter’s bracket scaffold A scaffold consisting of wood or metal brackets supporting a platform.

carpenter’s finish, Brit. joiner’s finish Finish work by a carpenter, including the laying of the finish flooring, the construction of stairs, the fitting and installation of doors and windows, exposed cabinet work and moldings, etc., but excluding rough finish work such as framing.

carpenters’ guides, carpenters’ handbooks See pattern book.

carpenter’s level An instrument used by a carpenter to determine a horizontal or a vertical line; consists of a spirit level set in a straight bar of wood or metal.

carpenter’s punch A nail set.

carpenter’s square, framing square A flat, steel square commonly used in carpentry.

carpentry A building trade which includes cutting, framing, and joining the timbers or woodwork of a building or structure.

carpet A heavy, durable floor covering, usually of woven, knitted, or needle-tufted fabric; commonly installed with tacks or staples, or by adhesives.

carpet backing The material on the underside of carpet; usually made of cotton, carpet rayon, kraft cord, or jute; may have a coating of latex.

carpet bedding Beds in which small annual plants with ornamental foliage or flowers, and perhaps gravel-filled sections as well, are arranged in patterns to be seen from above.

carpet construction Descriptive of the method by which a carpet is made, and how the pile fibers are fixed to the carpet backing; the construction is often classified as woven, tufted, or knitted.

carpet cushion Same as carpet underlayment.

carpet density The number of rows of pile tufts per inch, lengthwise.

carpet face weight The weight of carpet pile; in the US usually expressed in ounces per square yard of pile.

carpet fiber The material of which the yarn of the carpet pile is made, as wool, acetate, acrylic, cotton, nylon, polyester, polypropylene, rayon, etc.

carpet float A wood float, covered with a piece of dense-pile carpet; used in plastering to produce a fine-grained texture in a sand finish.

carpet installation See stretch-in carpet installation.

carpet pile The tufts of yarn that stand erect from the base of the carpet and whose ends form the surface; the ends may be cut or looped.

carpet pile height The height of the pile yarn above the backing material; usually expressed in inches or millimeters.

carpet pitch The number of warp yarn ends per inch crosswise of the loom; usually expressed in terms of the number of pile yarn ends in a 27-in. (68.6-cm) width of carpet.

carpet repeat In a roll of carpet which has a pattern, the distance from a specific point in a pattern figure to the same place where the figure occurs again, as measured lengthwise along the carpeting.

carpet strip 1. A molding used to fasten the edge of carpeting. 2. A strip of wood (approximately equal to the carpet thickness) installed on the floor at the threshold of a door.

carpet stuffers Extra yarn, usually jute, which is run lengthwise through the center of the fabric of carpet backing to add thickness and weight.

carpet tile A square piece of carpet used to cover a floor surface; commonly, such individual pieces are cemented to the floor with an adhesive to form a continuous surface.

carpet underlayment A padding material, laid directly on the floor, over which carpet is installed; usually manufactured of hair felt, foam rubber, hair felt and jute, sponge rubber, or some other combination of these materials.

carpet warp Yarn which runs lengthwise of the fabric, passing alternately over and under the weft yarns.

carpet weft Yarn which runs across the width of the carpet, from selvage to selvage.

car platform Same as elevator car platform.

carport A covered automobile shelter associated with a separate dwelling. It has one or more sides open to the weather.

carreau A single glass or encaustic tile, usually square or diamond-shaped, used in ornamental glazing.

carrefour 1. An open place from which a number of streets or avenues radiate. 2. By extension, any crossroad or junction. 3. A public square or plaza.

carrel, cubicle A small individual compartment or alcove in a library, used for semiprivate study.

carrelage Tiling; esp. the decorative tiling in terra-cotta used in the Middle Ages for floors, etc.; imitated in modern times.

carriage 1. An inclined beam which supports the steps or adds support between the strings of a wooden staircase, usually between the wall and outer string. Also called a carriage piece, horse, roughstring. 2. In theater stage equipment, a counterweight arbor. 3. A movable frame on which some other movable part or object is supported.

carriage bolt A threaded bolt having a circular head, an oval or flat bearing surface, and a means (such as a square shoulder under the head) of preventing rotation of the bolt.

carriage clamp A type of C-clamp used in carpentry.

carriage house See coach house.

carriage piece See carriage, 1.

carriage porch A roofed structure over a driveway at the door to a building, protecting from the weather those entering or leaving a vehicle. Also see porte cochere.

carriage shed A rough, roofed structure having one or more open sides; once used as a temporary shelter for horse-drawn carriages, as in the yard of a church.

carriageway (Brit.) A road designed to carry vehicular as opposed to pedestrian traffic; specifically, the actual traffic lanes of such a road as distinct from median strips or shoulders.

carrier 1. A mobile prime mover for transporting construction machines; also may serve as the working base or undercarriage of the machine. 2. A container attached to or hung from a trolley for moving a load from one point to another on a construction site. 3. A carrier angle or carrier bar which supports treads formed from metal grating.

carrier angle An angle iron connected to the inside face of a stair stringer to form a supporting ledge for the end of a tread or riser.

carrier bar A flat metal bar which is used in the same way as a carrier angle.

carrol Same as carrel.

carrying capacity Of an electric cable or wire, same as ampacity.

carrying channel In suspended ceiling construction, a three-sided metal member used to support the entire ceiling assembly.

carrying freezer A cold-storage room, where the temperature usually is maintained between −20°F (−28.9°C) and 20°F (−6.7°C).

carry up In masonry and brickwork, to build up a wall to a specified height.

car safety A mechanical device attached to an elevator car frame, or to the counterweight frame, designed to stop and hold the car or counterweight in case of a predetermined overspeed of the car or its free fall, or in the event that its hoisting ropes slacken.

car-switch operation Operation of an elevator car in which the movement and direction of travel of the car are directly and solely under the control of the operator by means of a manually operated car switch or continuous-pressure buttons in the car.

cart house An enclosure, such as a shed, for sheltering two-wheeled horse-drawn vehicles that are intended for two passengers.

cartload The quantity a cart will carry, usually ¼ to 1 cu yd (approx. 0.2 to 0.8 cu m).

carton pierre A mixture of glue, whiting, paper-pulp, and chalk; molded, dried, and finished to form durable, usually interior, architectural embellishments imitating stone, metal, etc.; a kind of papier-mâché used for making lightweight cast ornaments where plaster would be too heavy.

cartoon A drawing or painting made as a detailed model, often full-scale, of an architectural embellishment.

cartouche 1. An ornamental tablet often inscribed or decorated, and framed with elaborate scroll-like carving. 2. A modillion of curved form. 3. In Egyptian hieroglyphics and derivatives, a frame around the Pharaoh’s name.

cartridge Same as cartouche.

cartridge fuse A fuse enclosed in a cylindrical tube, which protects an electric circuit against the excessive flow of current.

cartridge heater An electric heating coil, enclosed in a metal case shaped like a cartridge.

cartridge-type filter A water filter in the form of a cartridge.

carved work 1. In stonework, hand-cut ornamental features which cannot be applied from pattern. 2. In brickwork, carving, usually on bricks of larger than ordinary size.

carvel joint A flush joint between adjacent planks.

caryatid A supporting member serving the function of a pier, column, or pilaster and carved or molded in the form of a draped, human, female figure. See canephora.

casa del campo In Spanish Colonial architecture and its derivatives, a one-story country house usually built around a patio, constructed primarily of adobe and wood; had a mission tile roof having a central ridge, or a shed roof having a single shallow pitch, usually with considerable overhang to provide shade.

casa del pueblo, casa del poblador In Spanish Colonial architecture of the 18th and 19th centuries, a house in a village or town usually constructed of adobe brick that has been plastered and whitewashed; had a mission tile roof supported by beams that penetrated the walls, and wood-framed casement windows, with the windows facing the street protected by grilles or gratings.

casa del rancho In Spanish Colonial architecture and its derivatives, especially in the 18th and 19th centuries, the main dwelling of a ranch that usually included: a large courtyard entered by way of a massive wooden gate; a corral; a partially enclosed or fully enclosed patio; living quarters for all members and servants of the household, housing for domestic animals, and associated storage spaces.

casa de tablas Same as tabla house.

cascade refrigerating system A refrigeration system consisting of two or more refrigerant circuits, each with a pressure-imposing element, condenser, and evaporator; the evaporator of one circuit cools the condenser of the other circuit, which is at a lower temperature.

case 1. To cover one building material with another. 2. Same as casing, 1. 3. The housing containing a lock mechanism. 4. A unit in which food is displayed and protected; often partially constructed of clear glass or plastic and thermally insulated; usually counter-top or wall-mounted.

case bay That section of a floor or roof between two principals or girders.

cased beam 1. A beam having a casing, 2. 2. Same as caged beam.

cased pile A concrete pile made by casting concrete within a steel casing placed into the ground; a cast-in-place pile.

cased-in timber Same as cased beam.

cased column Same as caged column.

cased frame, boxed frame, box frame The wood frame of a double-hung window; has hollow jambs or mullions which contain the sash counterweights.

cased glass, case glass, overlay glass Glass formed of two or more fused layers of different colors; the top layer may be cut, permitting a lower layer to show through.

cased opening, trimmed opening An opening between rooms which is finished with doorjambs and trim but does not have a door hung in it.

cased post A post having a casing, 2.

cased sash-frame A cased frame.

case-hardened 1. Said of a piece of material fabricated of steel or iron alloy whose surface has been hardened by a special process: first by carburization and then by heat treatment. 2. Said of timber whose outer layers have dried too rapidly during seasoning.

case-hardened glass Same as tempered glass.

case-hardening 1. In timber, a condition in which the outer layers have dried without shrinkage, causing stress between the inner and outer layers. 2. Producing a hard surface layer on steel, as by carburizing, cyaniding, carbonitriding, nitriding, induction hardening, and flame hardening.

casein A protein; the chief nitrogenous ingredient of milk.

casein glue Glue made from milk protein; esp. used in carpentry and joinery.

casein paint A paint made from a mixture of skimmed milk or buttermilk, earth-colored pigment, water, and a small amount of lime; widely used in the US and in Britain during the 18th and 19th centuries.

case lock A surface-mounted lock, such as a box lock.

casemate A vault or chamber in a bastion, having openings for the firing of weapons.

casemate wall A city or fortress enclosure consisting of an outer and an inner masonry wall braced by transverse masonry partitions, which divide the interstitial space into a series of chambers for fill or storage.

casement 1. A window sash (ventilator, 2) which swings open along its entire length; usually on hinges fixed to the sides of the opening into which it is fitted; see casement window. 2. A deep hollow molding, used chiefly in cornices.

casement adjuster A device for holding a casement in any open position. Also see casement stay.

casement combination window A combination window, 2, one element of which is a casement window.

casement door A French door.

casement fastener Same as casement stay.

casement hinge A hinge on which a casement, 1 is hung; also see butt casement hinge, close-up casement hinge, extension casement hinge.

casement stay In a casement window, a bar used to hold a casement, in any of several fixed, open positions. Also see peg stay.

casement ventilator A casement, 1, which opens like a door, supported on hinges, pivots, or friction hinge mechanisms.

casement window A window having at least one casement, 1; may be used in any combination with fixed lights.

casement sash Same as casement window.

caserne Same as barracks.

case mold A shell made of plaster to hold various parts of a plaster mold in proper position; also used to prevent distortion when pouring gelatin or wax molds.

case steel The outside skin on steel produced by case-hardening.

casework The aggregate assembled parts (including framework, finish, doors, drawers, etc.) which make up a case or cabinet.

cash allowance An amount established in the contract documents for inclusion in the contract sum to cover the cost of prescribed items not specified in detail, with provision that variations between such amount and the finally determined cost of the prescribed items will be reflected in change orders appropriately adjusting the contract sum.

cashel In Ireland, an enclosing wall of rough stone, once intended as defensive work for a church or for several sacred buildings; a caher.

casing 1. The exposed trim molding, framing, or lining around a door or window; may be either flat or molded. 2. Finished millwork, of uniform profile, which covers pipes or encases a structural member such as a post or beam. 3. A pipe section used to line a hole; may be driven, drilled, or dropped into place; also called a shell. 4. Of a pump, the housing that encloses the impeller.

casing bead A bead applied to edges of a plaster surface to provide a stop or a separation between two dissimilar materials.

casing-bead doorframe A doorframe having a metal casing bead which serves as a ground for plastering.

casing knife In paperhanging, a knife used to trim wallpaper around casings, at moldings, baseboards, etc.

casing nail A slender nail with a small, slightly flared head used for finishing work.

casing-off The elimination of the frictional forces between a portion of a pile, 1 and the surrounding soil by the use of a sleeve between the pile and the soil.

casino 1. A clubhouse or public room, esp. used for gambling. 2. A clubhouse or public room used for dancing. 3. A summerhouse or lodge; a retreat.

Cassel brown See Vandyke brown.

cassoon A deep panel or coffer in a ceiling or soffit.

cast glass Glass which is shaped by pouring molten glass into a mold.

cast, staff In plastering, a shape, usually decorative, made in a mold and then fastened in place.

castable refractory A packaged, dry mixture of hydraulic cement (generally calcium aluminate cement) and specially selected and proportioned refractory aggregates which, when mixed with water, produces refractory concrete or mortar.

castellated 1. Bearing the external fortification elements of a castle, in particular, battlements, turrets, etc. 2. Ornamented with a battlement-like or crenelated pattern.

castellated block A concrete block having a vertical, ribbed, decorative facing.

castellum A reservoir, often of architectural nature, at the end of an aqueduct, for distributing the water into various channels.

casting See founding.

casting bed A mold, often constructed of plywood or fiberglass, which is used to give a desired shape to poured concrete.

casting plaster A finely ground plaster with special additives; used in casting work. The additives produce hardness and control shrinkage or expansion.

cast-in-place concrete, in situ concrete Concrete which is deposited in the place where it is required to harden as part of the structure, as opposed to precast concrete.

cast-in-place pile A concrete pile which is concreted either with a casing or without a casing at its permanent location, as opposed to a precast concrete pile.

cast-in-situ concrete Same as cast-in-place concrete.

cast iron An iron alloy, usually including carbon and silicon; a large range of building products are made of this material by pouring the molten metal into sand molds and then machining. Has high compressive strength, but low tensile strength.

cast-iron architecture In building construction, cast iron used in combination with wrought iron for the framing of commercial buildings and for the components of cast-iron fronts; used primarily before the advent of steel-frame construction. Usually characterized by: prefabricated cast-iron components, repetitive modules, and large windows, in contrast to earlier masonry façades in which large windows were impractical because they weakened the wall into which they were set.

cast-iron boiler A boiler furnished in sections of cast iron, usually assembled at the place of installation; the capacity of the boiler may be increased by adding more sections.

cast-iron front A load-bearing façade composed of prefabricated parts, commonly used on commercial buildings ca. 1850–1870.

cast-iron lacework Mass-produced decorative ironwork of intricate design, formed by the casting process and therefore relatively inexpensive compared with wrought-iron work.

cast-iron pipe, cast-iron soil pipe A pipe fabricated of an iron alloy containing carbon and silicon; usually lined with cement or coal-tar enamel and coated externally with one of a variety of materials to reduce corrosion by soils; known technically as gray cast-iron pipe.

cast-iron register See mantel register.

cast-iron stove See Franklin stove.

castle A stronghold; a building or group of buildings intended primarily to serve as a fortified post; a fortified residence of a prince or nobleman. Also see concentric castle.

castlery The area around a castle that is subject to its domination.

cast molding A molding of plaster, cement, or other such material which is cast in a mold in sections and set in place after it has hardened.

castrum An ancient fortified town, castle, or fort.

cast staff In plastering, a shape, usually decorative, made in a mold and then fastened in place.

cast stone See artificial stone.

CAT. On drawings, abbr. for “catalog.”

cat A roll of straw and clay; used as filling between timbers in a wall.

catabasis, catabasion See katabasis.

catacomb Underground passageways used as cemeteries, with niches for sarcophagi or smaller ones for cinerary urns.

catacumba The atrium or courtyard of a basilican church.

catafalque A draped and canopied stage or scaffold, usually erected in a church, on which is placed the coffin or effigy of a deceased person.

catalyst 1. A substance which accelerates a chemical reaction but appears to remain unchanged itself. 2. A hardener that accelerates cure of adhesives either with or without heat. Used primarily with synthetic resins.

catalytically-blown asphalt A blown asphalt produced by using a catalyst during the blowing process.

cat-and-clay chimney Same as stick-and-clay chimney.

catch A device for fastening a door or gate; usually opened manually from one side only.

catch basin A reservoir, esp. for catching and retaining surface drainage over a large area, in which sediment may settle.

catch drain A drain running along sloping ground to catch and convey the water flowing over the surface.

catchment area Same as catch basin.

catch pit Same as catch basin.

catch platform A platform or other construction projection from the face of a building, from which it is supported; used to protect individuals and property from falling debris during construction.

catena d’acqua In landscape architecture, water which flows over a series of relatively narrow steps, forming a “staircase of water.”

catenary The curve formed by a flexible cord hung between two points of support.

catenary arch An arch which takes the form of an inverted catenary.

catenated Decorated by a chain-like motif.

caterpillar Same as crawler tractor.

catface A rough depression, flaw, or blemish in a plaster finish coat.

cathead A notched wedge placed between two formwork members meeting at an oblique angle.

cathedra The bishop’s throne, set at the end of the apse in Early Christian churches.

cathedral The home church of a bishop, usually the principal church in a diocese.

cathedral glass Translucent sheet glass which is unpolished.

cathedral precinct The grounds immediately surrounding a cathedral.

Catherine-wheel window A round window with radial mullions. A rose window, wheel window.

cathetus The axis of a cylinder, esp. the axial line passing through the eye of an Ionic volute.

cathodic corrosion Same as galvanic corrosion.

catholicon See katholikon.

cathodic protection, electrolytic protection A method of protecting a ferrous metal structure, which is embedded in water or moist soil, from corrosion due to galvanic action; usually by attaching it to a metal rod which is more electronegative than the structure, or by counteracting the current which is the source of corrosion by another one (in the opposite direction) which just balances it.

cation-exchange softening The softening of water by the removal of dissolved ionic contaminants in hard water (such as scale-forming magnesium and calcium ions) and their replacement with sodium ions, which are more soluble.

cat ladder, duckboard, gang boarding, roof ladder A plank with a series of small strips nailed across it; hung on a sloping roof under repair to provide a footing for workmen and to protect the surface.

cathedral: plan of Wells Cathedral. A, apse; B, altar; D, E, eastern transept; F, G, western transept; H, central tower; I, J, western towers; K, north porch; L, library; M, western doorway; N, N, western side doors; O cloister yard; P, Q, north and south aisles of choir; S, S, east and west aisles of transept; T, U, north and south aisles of nave; R, R, chapels; V, rood screen; W, altar of lady chapel

cat’s eye A pin knot smaller than ¼ in. (0.6 cm) in diameter.

catshead An ornament consisting of an animal-like head, similar to a beakhead.

catslide 1. The long sloping roof at the rear of a saltbox or catslide house. 2. The term used in southern US for a saltbox house.

catslide house A commonly used term in southern regions of the US for a saltbox house.

catstep See corbiestep.

CATW On drawings, abbr. for catwalk.

catwalk A narrow fixed walkway providing access to an otherwise inaccessible area or to lighting units, light bridges, etc.; used above an excavation, around a high building, above the ceiling of an auditorium or theater, or around a stagehouse.

catstone Same as barstone.

caul A flat sheet of metal or wood used as a protective layer of plywood, particleboard, fiberboard, etc., during the forming, pressing, and shaping operations.

cauliculus, caulicole Any one of the ornamental stalks rising between the leaves of a Corinthian or Composite capital, from which the volutes spring.

caulis One of the main stalks of leaves which spring from between the acanthus leaves of the second row on each side of the typical Corinthian capital, and which are carried up to support the volutes at the angles.

caulk To fill a joint, crack, etc., with caulking.

caulked joint A type of joint used for cast-iron pipe having hub-and-spigot ends. After the spigot-end of one pipe is placed inside the hub-end of the other, a rope of oakum or hemp is packed into the annular space around the spigot end until the packing is about 1 inch (2.5 cm) below the top. Then molten lead is poured into the annular space on top of the rope. Finally, the lead is pounded farther into the joint with a caulking iron.

caulked rivet A rivet which has not been properly driven so as to fit tightly in the hole, but to which a seeming tightness has been given by turning the edge of the head under with a cold cut or similar tool.

caulking, calking 1. A resilient mastic compound, often having a silicone, bituminous, or rubber base; used to seal cracks, fill joints, prevent leakage, and/or provide waterproofing; also see caulking compound. 2. Another term for cogging.

caulking cartridge An expendable container made of plastic, fiberboard, or metal; filled with caulking compound, for use in a caulking gun. A common type is 2 in. (5 cm) in diameter, approx. 8 in. (20 cm) long, and fitted with a plastic nozzle.

caulking compound A soft putty-like material intended for sealing joints in buildings and other structures, preventing leakage, or providing a seal at an expansion joint; usually available in two consistencies: “gun grade,” for use with a caulking gun, and “knife grade,” for application with a putty knife.

caulking ferrule A ferrule, usually of brass, which is caulked.

caulking gun A device for applying caulking compound by extrusion. In a hand gun, the required pressure is supplied mechanically by hand; in a pressure gun, the pressure required usually is greater and is supplied pneumatically.

caulking recess In plumbing, a recess (or counterbore) in the back of a flange into which lead can be caulked, for water pipe connections and the like.

causeway 1. A paved road or passage raised above surrounding low ground. 2. Such a passage ceremonially connecting the valley temple with the pyramid in Egyptian architecture.

caustic dip The immersion of metal in a chemical solution for cleaning purposes.

caustic embrittlement A type of embrittlement in the metal at joints and the ends of tubes in steam boilers; due to the chemical composition of the boiler water; may lead to failure of the metal.

caustic etch, frosted finish A decorative matte texture produced on aluminum alloys by an etching treatment in an alkaline solution, generally caustic soda.

caustic lime See lime.

cavaedium 1. An inner courtyard in a Roman house. 2. An atrium.

cavalier 1. A raised portion of a fortress for commanding adjacent defenses or for the placement of weapons. 2. A small tower on the ridge of a double-pitched roof.

cavasion A term, used many years ago, for an excavation for the foundation of a building.

cavea The semicircular, tiered seating area of an ancient (esp. Roman) theater.

cavel Same as kevel.

cavetto, gorge, hollow, throat, trochilus A hollow member or round concave molding containing at least the quadrant of a circle, used in cornices and between the tori of bases, etc. Erroneously called “scotia,” which has a noncircular curvature.

cavetto cornice See Egyptian gorge.

cavil Same as kevel.

cavitation A phenomenon in the flow of water consisting in the formation and the collapse of cavities in water.

cavitation damage The pitting of concrete caused by implosion (collapse) of bubbles in flowing water.

cavity barrier Same as fire stop.

cavity batten A piece of wood placed within a cavity wall during construction to catch mortar droppings.

cavity fill A material placed in the air space in a hollow or double wall or in a floor-ceiling assembly to improve its sound- or heat-insulation qualities.

cavity flashing A continuous sheet of waterproofing material which is installed across the gap of a cavity wall.

cavity tie See cavity wall tie.

cavity tray A British term for cavity flashing.

cavity wall, hollow masonry wall, hollow wall An exterior wall, usually of masonry, consisting of an outer and inner withe separated by a continuous air space, but connected together by wire or sheet-metal ties. The dead air space provides improved thermal insulation.

cavity wall tie A rigid, corrosive-resistant metal tie which bonds two withes of masonry.

cavity vent An opening in a stone veneer wall to permit air and moisture from inside the cavity wall to escape to the exterior.

cavo-rilievo, cavo-relievo See sunk relief.

cayola A hard plaster or stucco, similar to argamasa.

CB Abbr. for catch basin.

CB1S Abbr. for “center beam one side.”

CB2S Abbr. for “center beam two sides.”

CBM Abbr. for “Certified Ballast Manufacturers Association.”

CBR Abbr. for California bearing ratio.

C/B ratio, saturation coefficient The ratio of the weight of water absorbed by a masonry unit during immersion in cold water to weight absorbed during immersion in boiling water; an indication of the probable resistance of brick to freezing and thawing.

c-c Abbr. for “center-to-center.”

cc, CC Abbr. for “cubic centimeter.”

C-clamp A steel clamp, shaped like the letter C; used to hold, under pressure, two materials placed between the top of the open end of the C and a flattened end of a screw shaft which is threaded through the other end of the C.

CCTV Abbr. for “closed-circuit television.”

CCTV surveillance system See closed-circuit TV surveillance system.

CCW On drawings, abbr. for “counter-clockwise.”

cd Abbr. for candela.

cedar A durable softwood generally noted for decay resistance; includes western red cedar, incense cedar, eastern red cedar.

cedro In Spanish Colonial architecture, one of many unsplit peeled, relatively straight, red cedar saplings supported by vigas; used in ceiling construction.

ceil 1. To provide with a ceiling. 2. To provide with a wainscot finish; to sheathe internally.

ceiling The overhead surface of a room, usually a covering or decorative treatment used to conceal the floor above or the roof.

ceiling area lighting Lighting in which the entire ceiling acts as one large luminaire, as, for example, a luminous ceiling.

ceiling beam Same as ceiling joist.

ceiling binder An intermediate support for ceiling joists.

ceiling cable distribution system A cable distribution system in which cable is run through the space between a suspended or false ceiling and the structural floor above it.

ceiling cornice Same as cove molding.

ceiling diffuser, ceiling outlet 1. Any air diffuser (usually round, square, rectangular, or linear) which is located in the ceiling; used to provide a horizontal distribution pattern of air over a zone occupied by people.

ceiling fan A ceiling-mounted air-moving device that is characterized by several revolving blades (commonly three to five) which are comparatively large and slow-moving; usually hung so that it directs the air downward; relatively quiet in operation because of its low speed.

ceiling fitting Same as surface-mounted luminaire.

ceiling flange Same as escutcheon, 2.

ceiling floor The framework for a ceiling beneath, but not for the floor above.

ceiling hanger A hanger, 1 for supporting a room’s ceiling, usually by means of rods or wires. An elastomer or metal spring may be incorporated into the suspension to improve its sound isolation from the structure above; see illustration under resilient hanger.

ceiling height The clear vertical distance from the surface of the finished floor to the ceiling above it.

ceiling hook A hook having a wood screw formed in its base. (See illustration p. 186.)

ceiling joist 1. Any joist which carries a ceiling. 2. One of several small beams to which the ceiling of a room is attached. They are mortised into the sides of the binding joists, nailed to the underside of these joists, or suspended from them by straps.

ceiling light A borrowed light, 1, horizontally located in a ceiling to provide light below.

ceiling medallion, ceiling ornament, ceiling rose A ceiling ornament, usually cast in plaster; often a luminaire or chandelier is hung from its center; see medallion, 2.

ceiling outlet 1. A ceiling diffuser. 2. A small metal box, mounted at ceiling level, in which electric conductors terminate; used to support a lighting fixture or other ceiling-mounted electric appliance.

ceiling plenum In an air-conditioning system, the space between a hung ceiling and the underside of a floor slab above, where this space is used as a plenum for return air.

ceiling ratio In illumination engineering, the ratio of the luminous flux which reaches the ceiling directly to the upward component of the flux provided by a luminaire.

ceiling rose See ceiling medallion.

ceiling sound transmission In a suspended ceiling construction, the transmission of sound between adjoining rooms by way of the path consisting of the ceiling of each room and the continuous plenum over, and common to, both rooms.

ceiling sound transmission class, ceiling STC A single-number rating of the sound-insulating value of a suspended ceiling between adjacent rooms.

ceiling sprinkler A fire sprinkler (head) of special design, intended for installation in ceilings; includes sprinklers of the recessed, flush, and concealed types.

ceiling STC Same as ceiling sound transmission class.

ceiling strap A strip of wood, nailed to the underside of floor joists or rafters, from which a ceiling is suspended or fastened.

ceiling strut An adjustable vertical member which extends from the head of a doorframe to construction above; used to hold the frame in a fixed position prior to wall construction; also see strut guide.

ceiling suspension system A system of metal members designed to support a suspended ceiling, typically an acoustical ceiling. Also may be designed to accommodate lighting fixtures or air diffusers.

ceiling switch Same as chain-pull switch.

ceilure See celure.

celature Engraved, chased, or embossed decoration on metal.

cell 1. See core. 2. A single small cavity surrounded partially or completely by walls. 3. A segment of a ribbed vault. 4. The small sleeping apartment of a monk or a prisoner. 5. In electrical systems, a single raceway of a cellular or underfloor duct system. 6. In electrical batteries, a single voltage-producing component used in series with other similar components to provide the desired output voltage.

cella, naos The sanctuary of a classical temple, containing the cult statue of the god.

cellar 1. A room (or several rooms, or the entire basement floor) that is partially or entirely below grade; relatively cool in the summer and above freezing in the winter; often used as storage space; provides some thermal insulation airspace between the ground or concrete slab and the flooring of the wood floor above. 2. That part of a building having at least half of its clear height below grade. Also see earth cellar, root cellar, storm cellar, basement.

cellar bulkhead, cellar cap Same as bulkhead, 4.

cellar door A bulkhead, 4, often sloping or nearly horizontal.

cellar hole The excavation for a cellar or the open remains of a cellar.

cellarino In the Roman or Renaissance Tuscan or Doric orders of architecture, the neck or necking beneath the ovolo of the capital.

cellar rot Same as wet rot.

cellar sash A window sash set into the foundation wall of a building, usually just below the horizontal member or surface that provides bearing and anchorage for the wall above.

cellarway Passage to or through one or more cellars.

cellula 1. In ancient Rome, a small sanctuary in the interior of a small temple. 2. Any small chamber or storeroom.

cellular block A concrete masonry block which has uniformly distributed pores throughout its mass.

cellular brick (Brit.) A brick or block in which holes, closed at one end, exceed 20% of the volume.

cellular cofferdam A self-sustaining cofferdam fabricated of interlocking steel sheet piling; has separate inside and outside walls.

cellular concrete, aerated concrete A light-weight product consisting of portland cement, cement-silica, cement-pozzolan, lime-pozzolan, or lime-silica pastes, or pastes containing blends of these ingredients and having a homogeneous cell structure, produced by gas-forming chemicals or foaming agents.

cellular construction Construction with concrete elements in which part of the interior concrete is replaced by voids.

cellular-core door See mesh-core door.

cellular floor A floor having hollow openings in it that provide ready-made raceways for distributing wiring for telecommunications and electric power.

cellular framing See box frame, 1.

cellular glass See foam glass.

cellular material Any material that contains many cells (either open or closed, or both) dispersed throughout the mass.

cellular office A large floor space that is divided into a number of individual offices by permanent walls, in contrast to an open-plan office.

cellular plastic A plastic containing numerous cells disposed uniformly throughout its mass.

cellular polystyrene An insulation composed principally of a polymerized styrene resin which has been processed to form a rigid foam having a closed-cell structure.

cellular raceway A hollow space, in a modular floor system, suitable for use as a raceway for electric conductors.

cellular rot Same as wet rot.

cellular rubber A rubber product containing cells that are either open and interconnecting or closed and not interconnecting.

cellular striation In a cellular material, such as plastic, a layer of cells that differ greatly from the characteristic cell structure of the material.

celluloid A relatively tough thermoplastic material made from plasticized cellulose nitrate with camphor; inflammable, easily molded, readily dyed, not light-stable.

cellulose A naturally occurring polysaccharide made up solely of glucose units and found in most plants; the main constituent of dried woods, jute, flax, hemp, ramie, etc.; cotton is almost pure cellulose; used in the manufacture of a wide variety of synthetic building materials.

cellulose acetate A material of the ester family derived by conversion of cellulose; used in the production of synthetic lacquers, coatings, plastics, and thermal insulation.

cellulose acetate butyrate (CAB) plastic A plastic compound of cellulose acetate butyrate ester and plasticizer and other ingredients.

cellulose enamel Lacquer made with nitrocellulose. Also see lacquer.

cellulose fiber tile An acoustical tile formed of cellulose fiber.

cellulose lacquer A lacquer having a cellulose derivative base.

cellulose nitrate A material formed by the reaction of cellulose fibers with nitric and sulfuric acids. Those with lower nitrogen content are used as binders in lacquers and are very inflammable. A high nitrogen content results in nitrocellulose, an explosive.

cellure See celure.

Celsius scale Same as centigrade scale.

Celtic cross A cross with a long vertical shaft and short horizontal arms, and with a circle struck from their intersection, joining all four.

celure, ceilure, cellure A decorative ceiling, esp. over the chancel, in medieval church architecture or derivatives. 2. A paneled canopy above an altar or crucifix.

CEM On drawings, abbreviation for cement.

cem ab Abbr. for cement-asbestos board.

cement 1. A material or a mixture of materials (without aggregate) which, when in a plastic state, possesses adhesive and cohesive properties and hardens in place. Frequently, the term is used incorrectly for concrete, e.g., a “cement” block for concrete block. See also portland cement. 2. A calcined combination of limestone and clay, combined with an aggregate that reacts chemically when water is added; after this reaction occurs, the mixture hardens in place as it dries, resulting in a stonelike material. Although the ancient Romans developed a cement that could harden under water (called hydraulic cement), there was little information in modern times on how to produce such a cement until the mid-1700s when experiments in England led to the development of a cement that could set quickly, in or out of water. Also see hydraulic cement, portland cement, Roman cement, water cement.

cement-aggregate ratio The ratio, by weight or volume, of cement to aggregate.

cement-asbestos board A dense, rigid, noncombustible board containing a high proportion of asbestos fibers which are bonded with portland cement; highly resistant to weathering; also called asbestos-cement board.

cementation The setting of a cement.

cement bacillus See ettringite.

cement block See concrete block.

cement brick Brick fabricated from a mixture of cement and sand; molded under pressure and steam-cured at a temperature of 200°F (93°C); used behind face brick where it will not be exposed to acid or alkaline conditions.

cement clinker See clinker, 1.

cement-coated nail A nail which is coated with cement to increase its holding power.

cement content, cement factor The quantity of cement contained in a unit volume of concrete or mortar, preferably expressed as weight, but frequently given as bags of cement per cubic yard of concrete, e.g., a 6½-bag mix.

cemented soil Soil in which the particles are held together by a chemical agent.

cement factor See cement content.

cement fillet, weather fillet Mortar which provides a weathertight seal in a corner between roofing slates and a wall; used in place of flashing.

cement fondu Same as calcium aluminate cement.

cement gel A colloid comprising the largest part of the porous mass of mature hydrated cement paste.

cement gravel Gravel bound into a mass by clay, calcium carbonate, silica, or some other binding agent.

cement grout See grout.

cement gun A device for applying cement mortar as a spray; uses compressed air as the propellant.

cementitious Having cementing properties.

cementitious material A material (with or without an aggregate) that provides plasticity, cohesive, and adhesive properties when it is mixed with water—properties that are necessary for its placement and formation into a rigid mass.

cementitious mixture A mixture of mortar, concrete, or grout that contains hydraulic cement.

cement mixer See concrete mixer.

cement mortar A mixture of cement, lime, sand, or other aggregates with water; used for plastering over masonry or to lay blocks. The lime adds plasticity and resistance to moisture. Also see mortar.

cement paint, concrete paint 1. A paint consisting generally of white portland cement and water, pigments, hydrated lime, water repellents, or hygroscopic salts; usually applied over masonry surfaces as a waterproofing. 2. A paint formulated to be resistant to the alkali in the cement surface over which it is applied.

cement paste A mixture of cement and water.

cement plaster 1. Plaster with portland cement as the binder; sand and lime are added on job. Used for exterior work or in wet or high-humidity areas. 2. In some regions, gypsum plaster.

cement rendering The application of a portland cement and sand mix over a surface; has rather poor weather resistance.

cement rock, cement stone A clayey limestone whose percentage composition of alumina, lime, and silica is about that of cement; may be used without the addition of other earth materials.

cement screed A screed of cement mortar.

cement slurry A mixture of cement and water, still in the liquid state; injected into prepacked aggregate or used as a wash over a surface.

cement stucco Same as stucco.

cement temper Portland cement used as an additive in lime plaster to improve its strength and durability.

cement-water paint Same as cement paint.

cement-wood floor A poured floor of a mixture of portland cement, sand, and sawdust.

cemetery beacon In Europe in the 12th and 13th centuries, a model of a lighthouse having an altar.

cem. fin. Abbr. for “cement finish.”

CEM FL On drawings, abbr. for “cement floor.”

CEM MORT On drawings, abbr. for cement mortar.

CEM PLAS On drawings, abbr. for cement plaster.

cen Abbr. for “center” or “central.”

cenaculum In ancient Rome, a small informal dining room, often on an upper story.

cenatio In ancient Rome, the formal dining room in a house, sometimes even in a separate annex.

cenotaph A monument erected in memory of one not interred in or under it.

center 1. The center ply in plywood. 2. The core in a laminated construction. 3. Centering. 4. The center about which an arc of a circle is drawn, equidistant from all points on the arc.

center bit A tool for boring holes in wood, held by a brace; the cutting end consists of a sharp point (or threaded center spur) for fixing the center of the hole, a projecting scoring edge for marking the circumference of the hole, and a sharp lip for cutting away the wood inside the circumference.

center flower A molded plaster centerpiece.

center-gabled pediment A pediment on a gable located at the center of a façade; may be flush with the front wall or project forward from it.

center gutter Same as valley gutter.

center-hall cabin, central-hall cabin A cabin having two rooms that are separated by a hallway; often, there is an exterior chimney on each end wall. Compare with dogtrot cabin and saddlebag cabin.

center-hall plan In American Colonial architecture, the floor plan of a house usually having two rooms symmetrically situated on each side of a centrally located hallway; a stair in the hallway leading to the loft space above. Essentially a hall-and-parlor plan with a hallway separating the two rooms.

center-hung door, center-pivoted door A door which is supported by and swings about a pivot recessed in the floor at a point located on the center line of the door’s thickness; the door may be of the single-swing or double-acting type.

center-hung sash A window sash hung on its centers so that it swings about a horizontal axis.

centering A temporary structure upon which the materials of a vault or arch are supported in position until the work becomes self-supporting.

centering rafter The common rafter, directly adjacent to a hip rafter, that joins the longitudinal member at the apex of a roof.

center line A line representing an axis of symmetry; usually shown on drawings as a broken line.

center-matched Said of tongue-and-grooved lumber with its tongue-and-groove at the center of the piece rather than offset as in standard matched.

center nailing The nailing of slates (at a point just above their middle) along a line which is slightly above the head of the slates in the course below.

center of gravity, center of mass A point within a body such that, if the whole mass of the body were concentrated there, the attraction of gravity would remain the same.

center of mass See center of gravity.

center of twist See shear center.

center-opening door Same as biparting door.

centerpiece An ornament placed in the middle of something, as a decoration in the center of the ceiling.

center pivot Of a door: a pivot having its axis on the thickness center line of the door, normally about 2¾ in. (7 cm) from the hinge jamb.

center-pivoted door See center-hung door.

centerplank, heart plank Usually a quartersawn hardwood board cut near the center of a log.

center punch A hand-held punch consisting of a steel rod, one end of which has a sharp point; used to mark a point on metal, indicating where a hole is to be drilled.

center rail The horizontal door rail which separates the upper and lower panels of a recessed panel-type door; usually located at lock height.

centers See centering.

center shaft Of a revolving door, the vertical shaft to which the wings are attached.

center stringer A string, 1, which is located under a flight of stairs at its midpoint and which supports its treads by cantilever action.

center-to-center, on center The distance between the center line of one element, member, part, or component (as a stud or joist) and the center line of the next.

centi A prefix indicating division by 100.

centigrade The thermometer scale, divided into 100 degrees, in which 0°C is the freezing point of water and 100°C is the boiling point.

centigrade heat unit Same as pound-calorie.

centimeter In the metric system, a measure of length equal to a hundredth part of a meter, or 0.3937+ in.; abbreviated cm; an inch equals 2.54 cm.

central air-conditioning system An air-conditioning system in which the air is treated by equipment at one or more central locations outside the spaces served, and conveyed to and from these spaces by means of fans and pumps through ducts and pipes.

central air-handling unit An air-handling unit in which treated air is distributed to a number of spaces by means of ductwork.

central fan system A mechanical system of air conditioning in which air is treated by equipment outside the area served and distributed by means of ductwork.

central-hall plan, central-passage plan Same as center-hall plan.

central heating system A system in which heat is supplied to all areas of a building from a central plant through a network of ducts or pipes.

centralized HVAC system A heating, ventilating, and air-conditioning system having a single heating and/or cooling source for air distribution.

centralized structure A building having all its principal axes of equal length.

centrally located chimney, central chimney An interior chimney, often massive in size, located near the middle of a house, to provide heat for the entire house during the winter.

central-mixed concrete Concrete that is completely mixed in a stationary mixer, from which it is transported to the delivery point.

central mixer A stationary concrete mixer from which the freshly mixed concrete is transported to the work.

central newel In a spiral stair, the column around which the stairs are wound.

central pavilion A centrally located, prominent projection from the façade of a monumental public building or stately home; often two stories high and domed, and architecturally accented by more elaborate decorative elements.

central-plant refrigeration system A refrigeration system in which the cooling medium is distributed to remote locations from a central location, generally containing multiple refrigeration compressors and circulating pumps.

central-services core In a high-rise building, a central zone around which elevators, toilets, stairs, and service shafts are located.

central station An office to which one or more types of alarm systems in a building are connected; operators monitor and provide supervisory control of these systems; may be provided with direct lines to fire or police departments, or to other outside agencies.

centric load, concentric load A load which passes through the centroid of the cross section of a structural member and acts normal to the cross section.

centrifugal compressor A compressor in which compression is obtained by the use of a centrifugal pump.

centrifugal fan A fan, within a scroll-type housing, which receives air along the axis and discharges it radially; may be either belt-driven or connected directly to a motor.

centrifugally-cast concrete See spun concrete.

centrifugal pump A pump in which the pressure is imparted to the fluid by centrifugal force produced by a rotating impeller.

centring Same as centering.

centroid The point which may be considered the center of a two-dimensional figure; the center of gravity of an area.

centry-garth A burying ground or cemetery.

CEQ Abbr. for “Council on Environmental Quality.”

CER On drawings, abbr. for ceramic.

ceramic Any of a class of products, made of clay or a similar material, which are subjected to a high temperature during manufacture or use, as porcelain, stoneware, or terra-cotta; typically a ceramic is a metallic oxide, boride, carbide, or nitride, or a mixture or compound of such materials; hard, brittle, and an electrical insulator.

ceramic aggregate Ceramic products in lump or fragment form, usually colored, used in making ornamental concrete.

ceramic bond A bond between materials which are exposed to temperatures approaching the fusion point of the mixture, as a result of thermochemical reaction between the materials.

ceramic coating An inorganic, essentially nonmetallic protective coating on metal, suitable for use at or above red heat.

ceramic color glaze, ceramic glaze An opaque, colored glaze of satin or gloss finish; obtained by coating the clay body with a compound of metallic oxides, chemicals, and clays, either by spraying or by dipping, and then burning at high temperatures; the glaze is fused to the body, making them inseparable.

ceramic-faced glass Glass which during the heat-strengthening process has colored ceramic frit permanently fused to one surface.

ceramic tile 1. A glazed, 2 burned-clay product, having an impervious surface; widely used in plumbing systems. 2. A ceramic mosaic, 2.

ceramic veneer An architectural terra-cotta having a ceramic glazed surface; the dimensions of its face are usually large compared with its thickness; the backside glazing is either scored or ribbed, making it easier to attach the ceramic veneer to a wall or other surface.

cercis The wedge-like or trapezoidal section of seats between two of the stepped passageways in a Greek theater.

ceroma In a Greek or Roman bath, a room where bathers and wrestlers were anointed with oil thickened with wax.

certificate for payment A statement from the architect to the owner confirming the amount of money due the contractor for work accomplished or materials and equipment suitably stored, or both.

certificate of compliance A document issued by the responsible governmental authority stating that all of a building, or any designated portion thereof, complies with all provisions of applicable codes, statutes, and regulations.

certificate of insurance A memorandum issued by an authorized representative of an insurance company stating the types, amounts, and effective dates of insurance in force for a designated insured.

certificate of occupancy A document issued by governmental authority certifying that all or a designated portion of a building complies with the provisions of applicable statutes and regulations, and permitting occupancy for its designated use. Also called an occupancy permit or a certificate of use and occupancy permit.

certificate of substantial completion A certified statement, prepared by an architect on the basis of his inspection, (a) stating that the work, 1, or designated portion thereof, is substantially complete and ready for occupancy for its intended use; (b) establishing the date of substantial completion; (c) defining the interim responsibilities of the owner and the contractor for the provision of heat, maintenance, and security, and for possible damage and insurance; and (d) fixing the time within which the contractor shall complete the items on the inspection list (see punch list).

certificate of title A certificate issued by the appropriate land registration authority certifying that the land in question is lawfully owned; it describes the land and indicates any encumbrances upon it.

certification A declaration in writing that a particular product or service complies with a specification or stated criterion.

certified A term indicating that a testing laboratory, professional engineer, manufacturer, or contractor has formally confirmed that a material, device, or assembly of components conforms to the requirements of the applicable code.

certified ballast A fluorescent lamp ballast which adheres to performance standards set by the Certified Ballast Manufacturers Association.

Certified Ballast Manufacturers Association An independent organization of fluorescent lamp ballast manufacturers.

certified construction specifier A construction professional who, by experience and examination by the Construction Specifications Institute, has been certified as being proficient in the knowledge and art of preparing technical specifications for the building construction process.

certified output rating Same as gross output.

certosa A monastery of the Carthusian monks, esp. in Italy.

cesspit Same as cesspool.

cesspool 1. A lined and covered excavation in the ground which receives the discharge of domestic sewage or other organic wastes from a drainage system, so designed as to retain the organic matter and solids, but permitting the liquids to seep through the bottom and sides; also called a leaching cesspool or pervious cesspool. 2. (Brit.) A wooden box, usually lead-lined, constructed in a roof or gutter, to collect rainwater, which then passes to a downpipe.

CF 1. Abbr. for “cost and freight.” 2. Abbr. for “cooling fan.”

cfm Abbr. for “cubic feet per minute.”

CFR Abbr. for Code of Federal Regulations.

CG 1. Abbr. for “coarse grain.” 2. On drawings, abbr. for “ceiling grille.” 3. Abbr. for “corner guard.” 4. Abbr. for center of gravity.

CG2E Abbr. for “center groove two edges.”

chafer house Old English term for ale house.

chaff house A subsidiary building used on a farm to store fodder, such as corn husks, cut hay, or the like.

chain A land surveyor’s standard distance-measuring device. Also see Gunter’s chain.

chain block, chain fall, chain hoist A tackle, fitted with an endless chain for hoisting a heavy load by hand; often suspended from an overhead track.

chain bolt At the top of a door, a spring bolt which is actuated by a chain attached to it.

chain bond Masonry construction which is bonded together by an embedded iron bar or chain.

chain bucket loader A bucket-wheel excavator in which the buckets are on a roller chain.

chain course A bond course formed by stone headers which are held together by cramps.

chain door fastener A device attached to a door and its jamb which limits the door opening to the length of the chain.

chain-driven machine A machine connected by chain to a reversible motor or engine; for example, a chain-driven elevator.

chaînes 1. A type of wall decoration used in 17th century French domestic architecture; consists of vertical bands of rusticated masonry which divides the façades into panels or bays. 2. Same as quoin.

chain fall See chain block.

chain hoist See chain block.

chaining In surveying, the measuring of a distance by use of a chain or tape.

chaining pin, surveyor’s arrow, taping arrow, taping pin A metal pin used in surveying for marking taped measurements on the ground.

chain intermittent fillet weld Two lines of intermittent fillet welds on a joint, one line being approximately opposite the other.

chain link fence A fence made of heavy steel wire fabric (usually coated with zinc, or the like) which is interwoven in such a way as to provide a continuous mesh without ties or knots, except at the selvage; the wire fabric is held in place by metal posts.

chain molding A molding carved with a representation of a chain.

chain-pipe vise A portable vise used to hold pipe in the jaw by means of a chain.

chain pipe wrench, chain tongs A plumber’s wrench for turning pipe, consisting of a lever arm which has sharp teeth that engage the pipe and a short, adjustable chain which is wrapped around the pipe and holds the pipe securely.

chain-pull switch An electric switch, used in interior wiring, which is operated by pulling a chain or cord; usually mounted on the ceiling.

chain pump A pump consisting of an endless chain, fitted at intervals with disks, which moves through a pipe; used to raise sludge.

chain riveting Riveting in which the rivets are set in parallel adjacent rows along the seam and are not staggered.

chain saw A power-driven saw, usually handheld, for cutting wood; a protruding arm carries an endless chain, into which the cutting teeth are set.

chain scale A draftman’s scale or an engineer’s scale which is graduated in inches, which are further subdivided by 10 and multiples of 10.

chain timber A large bond timber.

chainwire The fabric from which a chain link fence is woven.

chair 1. A bar support. 2. A metal frame, built into a thin partition wall and the floor to support a sanitary fixture (such as a washbasin or water closet) clear of the floor. 3. A device used to support reinforcing bars.

chair board Same as chair rail.

chair house Same as cart house.

chairlift An electrically-operated lift for conveying a single passenger, who is seated in a chair, up or down the incline of a flight of stairs; in a private residence from one floor level to the next, or in a commercial building to meet the conditions of the Americans with Disabilities Act.

chair rail A horizontal strip usually of wood, affixed to a plaster wall at a height which prevents the backs of chairs from damaging the wall surface.

chair rail cap See cap, 3.

chaitya A Buddhist or Hindu sanctuary, shrine, or temple.

chaitya hall A hall of worship adjacent to a Buddhist monastery.

chalcedony A submicroscopic variety of fibrous quartz, generally translucent and containing variable amounts of opal; reacts with alkalies in portland cement.

chalcidicum, chalcidic 1. A portico, or hall supported by columns, or any addition of like character connected with any ancient basilica; hence a similar addition to a Christian church. 2. In a Christian basilica, the narthex. 3. In ancient Roman architecture, a building for judicial functions.

chalcidium A committee room off the main part of an ancient Roman lawcourt (basilica).

chalet 1. A timber house especially found in the Alps, distinguished by the exposed and decorative use of structural members, balconies, and stairs. Upper floors usually project beyond the stories below. 2. Any building of similar design. See Swiss cottage architecture.

chalk A soft limestone, usually white, gray, or buff in color, composed chiefly of the calcareous remains of marine organisms.

chalkboard A marking surface, primarily for use with chalk, which is cleanable and reusable.

chalkboard trim A chalkboard frame, operating hardware, and accessories.

chalked See chalky.

chalking The formation of a powdery surface condition from the disintegration of a binder or elastomer, as in a coating such as cement paint. The binder is decomposed and the pigment is loosely bound on the surface and resembles chalk when the finger is rubbed over it; caused by weathering or an otherwise destructive environment.

chalk line 1. A light cord rubbed with chalk and stretched over a surface to mark a straight line. 2. A line so marked. 3. Same as fat lime.

chalky, chalked Descriptive of the condition of a porcelain enameled surface that has lost its natural gloss and become powdery.

CHAM On drawings, abbr. for chamfer.

chamber 1. A room used for private living, conversation, consultation, or deliberation, in contrast to more public and formal activities. Also see bedroom, boudoir, cabinet, closet, den, parlor, solar, study. 2. A room for such use which has acquired public importance, e.g., the senate chamber, an audience chamber. 3. (Brit., pl.) A suite of rooms for private dwelling. 4. (pl.) A suite of rooms for deliberation and consultation (juristic). 5. A space equipped or designed for a special function, mechanical or technological, e.g., a torture chamber, a combustion chamber.

chamber story In a house, a floor completely occupied by bedrooms; also called chamber floor.

chamber test A fire test for floor coverings, developed by Underwriters’ Laboratories, Inc., in which speed and distance of flame spread are measured.

chamber tomb See passage grave.

chambered hall A house, having a one-room plan, which is two stories in height.

chambranle A structural feature, often ornamental, enclosing the sides and top of a doorway, window, fireplace, or similar opening. The top piece or lintel is called the transverse and the side pieces or jambs the ascendants.

chambrel An obsolete term for gambrel.

chamfer 1. A bevel or cant, such as a small splay at the external angle of a masonry wall. 2. A wave molding. 3. A groove or furrow. 4. An oblique surface produced by beveling an edge or corner, usually at a 45° angle, as the edge of a board or masonry surface.

chamfer bit A bit for beveling the upper edge of a hole.

chamfered rustication Rustication in which the smooth face of the stone parallel to the wall is deeply beveled at the joints so that, where two stones meet, the chamfering forms an internal right angle.

chamferet, chamfret 1. A hollow chamfer. 2. A hollow channel or gutter.

chamfer plane A carpenter’s plane esp. used for beveling edges; has a V-groove along the bottom or adjustable guides to facilitate the cutting of chamfers.

chamfer stop 1. Any ornamentation which terminates a chamfer. 2. A stop chamfer.

chamfer strip A cant strip.

champ A defined surface ready for carving.

champfer Same as chamfer.

chancel The sanctuary of a church, including the choir; reserved for the clergy.

chancel aisle The side aisle of a chancel in a large church; it usually passes around the apse, forming a deambulatory.

chancel arch An arch which, in many churches, marks the separation of the chancel or sanctuary from the nave or body of the church.

chancellery, chancellory 1. A chancellor’s office or a building containing one. 2. The official premises of a diplomatic envoy abroad.

chancel rail The railing or barrier in place of a chancel screen by which the chancel is separated from the nave.

chancel screen Screen dividing the chancel from the nave.

chancery A building or suite of rooms designed to house any of the following: a lawcourt with special functions, archives, a secretariat, a chancellery.

chandelier A luminaire suspended from the ceiling; usually ornate or branched with the lamps visible.

chandlery, chandry A storage room for lighting supplies and devices, required before gas or electricity was available.

chandry See chandlery.

change In building construction, an authorized alteration or deviation from the design or scope of work as originally defined by the contract documents.

change of use An alteration in the permitted use of an existing building; such a change may result in the imposition of other provisions of the applicable code, for example, those governing means of egress from the building.

change order A written order to the contractor signed by the owner and the architect, issued after the execution of the contract, authorizing a change in the work or an adjustment in the contract sum or the contract time as originally defined by the contract documents; may add to, subtract from, or vary the scope of work. A change order may be signed by the architect alone (provided he has written authority from the owner for such procedure and that a copy of such written authority is furnished to the contractor upon request), or by the contractor if he agrees to the adjustment in the contract sum or the contract time.

changeover point The temperature at which the thermal transmission loss to the outside of a building equals the heat gain in the interior, so that cooling or heating is not required.

changes in the work Changes ordered by the owner consisting of additions, deletions, or other revisions within the general scope of the contract, the contract sum and the contract time being adjusted accordingly. All changes in the work, except those of a minor nature not involving an adjustment to the contract sum or the contract time, should be authorized by change order. Also see field order.

channel 1. A structural or rolled steel shape used in steel construction. 2. A decorative groove, in carpentry or masonry. 3. An enclosure containing the ballast, starter, lamp holders, and wiring for a fluorescent lamp, or a similar enclosure on which filament lamps (usually tubular) are mounted.

channel bar See channel iron.

channel beam A structural member having a U-shaped cross section.

channel block A hollow concrete masonry unit with portions depressed to form a continuous channel for reinforcing steel and grout.

channel clip 1. In a ceiling suspension system, a metal clip which is hung from a channel and to which a perforated metal pan is attached. 2. A special fastener made of light-gauge sheet metal or wire for the attachment of gypsum lath, or the like, to steel channels.

channel glazing A method of window glazing which uses removable, surface-mounted, U-shaped metal stops or beads to fix the glass in place.

channeling A series of grooves in an architectural member, such as a column.

channel iron, channel bar A rolled iron or steel bar whose U-shaped cross section is formed by a broad central section, called a “web,” with a flange on either side.

channel mopping See strip mopping.

channel pipe A drain pipe having a half or three-quarter circular cross section; open along the top.

channel runner A heavy horizontal member in suspended ceiling construction.

channel section Same as channel, 1.

chantlate A piece of wood fastened to the rafters at the eaves and projecting beyond the wall, so as to prevent rainwater from trickling down the face of the wall.

chantry A chapel within a church, endowed for religious services for the soul of the donor or others he may designate.

chantry chamber The room or rooms used by the priest(s) attached to a chantry.

chapel 1. A small area within a larger church, containing an altar and intended primarily for private prayer. 2. A room or a building designated for religious purposes within the complex of a school, college, hospital, or other institution. 3. A small secondary church in a parish.

chapel of ease A church built within the bounds of a parish for the attendance of those who cannot reach the parish church conveniently.

chapel royal The chapel of a royal castle or palace.

chapiter Same as capital.

chaplet An astragal or bead molding, sometimes enriched with carved foliage.

chapter house A place for business meetings of a religious or fraternal organization; occasionally also contains living quarters for members of such a group.

chaptrel A small capital of a vaulting shaft.

charcoal filter A filter for removing odors, vapors, and dust particles from air, employing activated charcoal as the filter element.

charette 1. The intense effort to complete an academic architectural problem within a specified time. 2. The time in which this work is done.

charge The quantity of refrigerant in a refrigeration system.

charging Feeding materials into a concrete or mortar mixer, furnace, or other receptacle where they will be further treated or processed.

charging chute An enclosed vertical chute with doors through which waste material is dropped down and fed into an incinerator.

charging door A door to an incinerator through which waste is passed into the combustion chamber.

Charleston house An 18th- or early-19th-century town house in Charleston, South Carolina; usually Georgian or Greek Revival style, two stories high, with the first story often well above ground level. Such houses were of two types. The first and more common type, called a single house, was long and narrow, a single room deep, built with its long side perpendicular to the street; on the long side facing a garden was a two-tiered colonnaded porch onto which all rooms opened; the entrance was by a flight of stairs leading from the street up to the porch. The second type, called a double house, had a façade facing the street and was two rooms deep, boxlike in shape, and had a portico with a classical two-tiered porch in the middle of the façade.

charnel house A building or chamber for the deposit of the bones of the dead.

Charonian steps, Charon’s staircase In the early Greek theater, a flight of steps from the middle of the stage to the orchestra; used by characters from the underworld.

Charpy test A single-blow impact test utilizing a falling pendulum which breaks a specimen, usually notched, supported at both ends.

Chartered Building Surveyor A building surveyor who is a member of the Royal Institution of Chartered Surveyors.

chartered builder In Britain one who has been admitted as a member or fellow of the Chartered Institute of Building.

chartered engineer An individual who is a full member of one of the chartered engineering institutions.

Chartered Institute of Building In Britain, an institution open to all professionals in the field of building.

Chartered Institute of Building Services A British organization members whose are concerned with services within a building related to the building environment, including: heating, air-conditioning, lighting, acoustical, water supply services, drainage services, electrical supply, gas supply, fire protection, and security protection.

charterhouse A Carthusian monastery.

chartophylacium A place for the safe keeping of records and other valuable documents.

chartreuse A monastery of the Carthusian monks, esp. in France.

chase 1. A continuous recess built into a wall to receive pipes, ducts, etc.; a wall chase. 2. A groove cut in a masonry wall to receive a pipe, conduit, etc. 3. To decorate metalwork by tooling on the exterior surface.

chase bonding Joining old masonry work to new by means of a bond having a continuous vertical recess the full height of the wall.

chase mortise, pulley mortise A stub mortise which is larger than the tenon inserted into it; one side of the mortise is sloped, permitting the tenon to be inserted sideways; used where exterior clearance is limited.

chase wedge A wedge-shaped tool with a handle; used for bossing sheet lead.

chase tenon A tenon that can be inserted into its chase mortise, either laterally or lengthwise.

chasovnya In early Russian architecture, a chapel which is a detached structure.

chasse A container for a saint’s relics.

chat A stony mineral material, occurring with mineral ore; very similar to chert.

château 1. A castle or imposing country residence of nobility in old France. 2. Now, any French country estate.

château d’eau At the termination of an aqueduct, a reservoir architecturally embellished as a public fountain.

Châteauesque style, Château style, Châteauesque Revival An opulent architectural style patterned after the design of monumental French chateaus of the 16th century; popular in the late 19th century and beyond. Buildings were usually characterized by a façade having masonry walls; an attic story; a single balcony or continuous balconies; prominent use of vertical elements such as pilasters; wall dormers with gables that might break the roof line; cross gables; a belt course; an ornately hipped roof either steeply pitched to a ridge and/or truncated by a horizontal surface; cast-iron cresting on the roof; through-the-cornice wall dormers; roof dormers with pedimented parapets, pinnacles, and spires; a cylindrical corner turret having a conical roof; tall, decorative chimneys and ornamental chimney caps; windows, frequently in pairs, divided by heavy stone mullions; oriels; semicircular bay windows; exterior door set arches; often a canopy was provided over the entry door.

châtelet A castle of small scale.

chat-sawn finish In stone masonry cutting, the moderately rough surface resulting from the use of coarse chat (crushed chert) as the abrasive agent carried by the gang saw blades.

chattel 1. Any article of property not consisting of or affixed to land; movable property. 2. Same as 1, above, plus any interest in land that is less than a freehold. When this nomenclature is used, the term chattel personal is employed to designate movables such as goods and money, and chattel real to designate less-than-freehold interests in real property, such as leasehold interests for a term of years.

chattel mortgage A security interest in a chattel as collateral for the payment of a loan.

chatter marks Intermittent transverse marks on a material due to vibration during rolling, extrusion, cutting, or drawing.

chattra Atop a stupa, a stone umbrella symbolizing dignity; composed of a stone horizontally oriented disk on a vertical pole.

chattravali Similar to a chattra, but having three horizontally oriented stone disks; a triple umbrella; see illustration for stupa.

chauntry Same as chantry.

cheapener An extender in paint; not necessarily cheap; more expensive extenders may be used to provide such properties as hardness, wearability, gloss control, and improved brushability.

check 1. A small crack running parallel to the grain in wood and across the rings; usually caused by shrinkage during drying; in veneers, may improve the appearance. 2. A minute crack in steel which has been cooled too abruptly. 3. An attachment that limits movement, such as a door check. 4. See checking.

check cracks See checking.

check dam A barrier in an erodible channel to control the flow of water.

checked back Having a rabbet; receding.

checker, chequer One of the squares in a check pattern, contrasted to its neighbors by color or texture; often only two effects are alternated, as in a chessboard. Also see diaper.

checkered plate 1. A cast steel or iron plate having square, flat projections suggestive of a checkerboard. 2. A floor plate.

checkerwork In a wall or pavement, a pattern formed by laying masonry units so as to produce a checkerboard effect.

check fillet On a roof, a curb used to divert or control the flow of rainwater.

checking, check cracks, map cracks, shelling 1. Shallow cracks at closely spaced but irregular intervals on the surface of mortar or concrete. 2. Small cracks in a film of paint or varnish which do not completely penetrate to the substrate or the previous coat. The cracks are in a pattern roughly similar to a checkerboard. 3. In plastering, in a lime finish coat, fine spider-web cracks or fissures; usually caused by insufficient troweling or undergauging. 4. See check. 5. Very small cracks in a flat glass surface, usually along an edge.

checking floor hinge A door pivot, fixed in the floor, which includes a mechanism for controlling the speed of the door as it closes.

checking resistance The ability of a paint coating, or the like, to resist slight breaks that do not penetrate to the previously applied coating or substrate.

check lock A small lock whose function is to check the bolt of a larger lock that secures a door.

check nut Same as locknut, 2.

check rail In a double-hung window, a horizontal meeting rail esp. one which overlaps the other meeting rail.

checkroom A cloakroom, 3.

check stop A strip or molding used to hold a sliding element in place, as at the bottom sash of a double-hung window.

check strip A parting bead.

check throat A groove cut on the underside of a windowsill or doorsill to prevent the passage of drops of rainwater to the wall.

check valve, back-pressure valve, reflux valve An automatic valve which permits liquid to flow in only one direction. Also see non-return valve.

cheek 1. A narrow upright face forming the end or side of an architectural or structural member, or one side of an opening. 2. A narrow upright face forming the end or a side of an architectural or structural member. 3. The upright face of one side of an opening.

cheek boards In concrete formwork, the boards on the sides of the form.

cheek cut, side cut An oblique angular cut at the lower end of a jack rafter or the upper end of any rafter so that it can fit tightly against a hip rafter or valley rafter.

cheesiness The characteristic of a partially dried paint film which results in tearing and crumbling when pulled with the fingernail.

chemical bond A bond obtained as a result of cohesion between layers of similar crystalline materials, owing to the formation and the interlocking of crystals.

chemical brown stain See kiln brown stain.

chemical closet See chemical toilet.

chemical flux cutting An oxygen-cutting process wherein the severing of metals is effected by the use of a chemical flux to facilitate cutting.

chemical grout A fluid used in the chemical stabilization of soils.

chemically foamed plastic A cellular plastic whose structure is produced by gases generated from the chemical interaction of its constituents, as a foamed plastic.

chemically prestressed cement An expansive cement which contains a higher percentage of expansive component than shrinkage-compensating cement.

chemically prestressed concrete A concrete made with expansive cement and reinforcement under conditions such that tensile stress is induced in the reinforcement as a result of the expansion of the cement, so as to produce prestressed concrete.

chemical plaster Same as patent plaster, 2.

chemical-resistant paint A specially formulated paint finish which utilizes binders and pigments that are unaffected by chemicals.

chemical stabilization The injection of chemicals into a soil to improve its strength and decrease its permeability.

chemical staining Treatment of wood with chemicals to obtain color change and enhance grain contrast.

chemical toilet, Brit. chemical closet A toilet without conventional water and drain connections; contains a fluid, usually with a disinfectant and deodorant, which neutralizes waste matter chemically.

chemin-de-ronde A continuous gangway behind a rampart, providing a means of communication along a fortified wall.

chemise A wall (often concentric with the keep) built around a medieval fortification of a bastion or keep.

cheneau 1. A gutter at the eaves of a building, esp. one that is ornamented. 2. An ornamented crest, 2 or cornice.

chequer See checker.

cherry An even-textured, moderately high-density wood of the eastern US, rich red-brown in color; takes a high luster; used for cabinet

cherry mahogany See makore.

cherry picker A machine for lifting men or materials on a platform at the end of an extendable boom; usually mounted on a carrier with wheels to provide mobility.

chert A very fine-grained dense rock consisting of chalcedony or opal, often with some quartz, and sometimes with calcite, iron oxide, organic matter, or other impurities; has a homogeneous texture and white, gray, or black color; some of its constituents may react with cement alkalies and therefore may be undesirable as concrete aggregate for exposed concrete in northern climates.

chestnut A light, coarse-grained, medium-hard timber; used for ornamental work and trim.

cheval-de-frise, pl. chevaux-de-frise Sharply pointed nails or spikes set into the top of a barrier.

chevet The apse, ambulatory, and radiating chapels of a church.

chevron 1. A V-shaped stripe pointing up or down, used singly or in groups in heraldry and on uniforms; hence, any ornament so shaped. 2. A molding showing a zigzag sequence of these ornaments in Romanesque architecture or derivatives; a dancette or zigzag molding.

chevron pattern A V-shaped zigzag pattern used as an ornament in brickwork bond.

chevron slat A V-shaped slat used in an opening to provide privacy and ventilation.

Chicago Commercial style See Commercial style.

Chicago cottage A small, narrow, inexpensive, quickly built cottage set on a brick foundation with its lower story partially below ground level; characterized by balloon framing, clapboard exterior walls, an exterior stair between the street and a second-story entrance, an attic above the second story; developed for speculation in Chicago in the mid- to late 1800s.

Chicago School A group of highly influential architects, including Adler and Sullivan, Burn-ham and Root, William LeBaron Jenney, and their followers in Chicago in the latter part of the 19th century. The School’s central philosophy was that architectural design should be of its time rather than based on the past. This group initially applied its philosophy to both skyscrapers and homes, but its greatest and most lasting influence was in the design of skyscrapers, and its greatest achievements were in structural design. Also see Prairie School.

Chicago window A large plate-glass window in a commercial building with an operable window on each side to provide ventilation; because of its large size, it provided greater natural illumination than earlier windows. Widely used in high buildings in Chicago in the late 19th century.

chicken house See poultry house.

chicken ladder Same as crawling board.

chicken wire A light-weight, galvanized wire netting having a hexagonal mesh.

chien A standard unit of floor space or bay of a Chinese dwelling.

chien-assis A small unglazed dormer window used to provide light and ventilation in an attic below a sloping roof; especially used in the middle ages.

chigi On the roof of a Shinto temple, a decorative pair of curved timbers that extend above and beyond the roof ridge, crossing at the ridge.

chilled-water refrigeration system A refrigeration system employing water as the circulating liquid.

chiller Mechanical equipment used to circulate chilled water throughout a building; consists of a compressor, condenser, and evaporator.

chilling On a painted or varnished surface, a clouding of the surface or a reduction of luster as a result of the movement of cold air over the drying surface.

CHIM On drawings, abbr. for chimney.

chimney An incombustible vertical structure containing one or more flues to provide draft for fireplaces, and to carry off gaseous products of combustion to the outside air from fireplaces, furnaces, or boilers. Also see clay-and-sticks chimney, double chimney, double-shouldered chimney, end chimney, flush chimney, mudand-sticks chimney, outside chimney, pilastered chimney, sloped-offset chimney, stepped-back chimney, sticks-and-clay chimney, diagonal chimney stacks.

chimney apron A nonferrous metal flashing built into the chimney masonry and roofing at the penetration of the roof by the chimney.

chimney arch The arch over the opening of a fireplace, supporting the breast.

chimney back See fireback.

chimney bar, turning bar A wrought-iron or steel lintel which is supported by the sidewalls and carries the masonry above the fireplace opening. If curved, it is known as an arch bar.

chimney block A solid concrete masonry unit with curved faces, intended for use with other similar units in laying up a round flue.

chimney board Same as fireboard.

chimney bond A stretcher bond used in internal construction in chimneys.

chimney breast, chimney piece A projection into a room of fireplace walls forming the front portion of the chimney stack.

chimney can A chimney pot.

chimney cap, bonnet 1. An abacus or cornice forming a crowning termination of a chimney. 2. A rotary device, moved by the wind, which facilitates the escape of smoke by turning the exit aperture away from the wind, preventing the entry of rain or snow and improving the draft. 3. A chimney hood.

chimney cheek The sides of a fireplace opening which generally support the mantelpiece.

chimney connector A pipe or metal breeching which connects and makes the transition from furnaces and boilers to the flue of a chimney.

chimney corner, inglenook, roofed ingle An area adjacent to the hearth, usually provided with seating.

chimney cowl A revolving metal ventilator over a flue which induces updrafts and prevents downdrafts; a chimney cap, 2.

chimney crane A pivoted arm of cast iron attached to the rear wall of the fireplace upon which to hang pots for cooking.

chimney cricket A small false roof built over the main roof behind a chimney; used to provide protection against water leakage where the chimney penetrates the roof.

chimney crook, chimney hook In a fireplace, a cast-iron bar, hooked at the lower end and adjustable in length, upon which to suspend pots from a crane or other support.

chimney effect, flue effect, stack effect The tendency of air or gas in a shaft or other vertical passage to rise when heated, owing to its lower density compared with that of the surrounding air or gas.

chimney flue See flue.

chimney foundation A very large substructure, in a cellar, that supported the load of a huge fireplace and massive centrally located chimney and transmitted this load to the earth or rock below; such a foundation was necessarily immense because of the heavy load of the fireplace above it. Usually rectangular in shape and constructed of brick, stone, fieldstone, stone rubble, or some combination thereof.

chimney girt In a timber-framed house, a structural framing timber that served as a main horizontal support between chimney posts.

chimney gutter A preformed nonferrous metal flashing, used for waterproofing where a chimney pierces a pitched roof.

chimneyhead The top of a chimney.

chimney hood A covering which protects a chimney opening.

chimney hook A device for hanging pots for cooking; see chimney crane.

chimney jamb One of the two vertical sides of a fireplace opening.

chimney lining See flue lining.

chimney lug Same as randle bar.

chimney mantel See mantelpiece, chimney piece.

chimney pent A small structure, set flush between two exterior brick chimneys located on an end wall of a house; covered by a small narrow sloping roof at the level of the ground floor ceiling, buttressing the chimneys.

chimney piece An ornament over and around a fireplace framing the mantel or the casing of the chimney breast.

chimney post In a timber-framed house, one of the wood posts providing the main vertical structural supports at the front and rear sides of a chimney.

chimney pot, chimney can A cylindrical pipe of brick, terra-cotta, or metal placed atop a chimney to extend and thereby increase the draft.

chimney shaft That part of a chimney which is carried above the roof of a building of which it forms a part.

chimney stack 1. A group of chimneys carried up together. 2. A very tall chimney, usually round in cross section, attached to factories, mills, etc.

chimney stalk Same as chimney stack.

chimney terminal Same as chimney cap.

chimney throat, chimney waist The narrowest portion of a chimney flue, between the “gathering” (or upward contraction above the fireplace) and the flue proper; often where the damper is located.

chimney tile Same as fireplace tile; see also Dutch tile.

chimney top That part of a chimney that extends above the roof or crowns the chimney stack.

chimney tun A chimney stack.

chimney waist Same as chimney throat.

chimney wing Same as chimney cheek.

China grass cloth Same as grass cloth.

china sanitary ware Glazed, vitrified, sanitary ware.

China white See silver white, 2.

China wood oil See tung oil.

chinbeak molding One consisting of a convex followed by a concave profile, with or without a fillet below or between, as an inverted ogee, or an ovolo, fillet, and cove.

Chinese architecture A highly homogeneous traditional architecture which repeated throughout the centuries established types of simple, rectangular, low-silhouetted buildings costructed according to fixed canons of proportions and construction methods. Stone and brick were used for structures demanding strength and permanence, such as fortifications, enclosure walls, tombs, pagodas, and bridges. Otherwise buildings were mostly constructed in a wooden framework of columns and beams supported by a platform, with nonbearing curtain or screen walls. The most prominent feature of the Chinese house was the tile-covered gabled roof, high-pitched and upward-curving with widely overhanging eaves resting on multiple brackets. Separate roofs over porches surrounding the main buildings or, in the case of pagodas, articulating each floor created a distinctive rhythmical, horizontal effect.

Chinese blue 1. A pigment in the iron blue family. 2. One type of Prussian blue.

Chinese bond Same as rat-trap bond.

Chinese Chippendale Descriptive of lattice patterns suggestive of Chinese motifs designed by Thomas Chippendale (1718–1779), England’s most widely known furniture maker of his time. Such designs were a combination of horizontal, vertical, and diagonal lines, forming geometric patterns, usually within a rectangular frame; especially used in railing systems.

Chinese fret A lattice pattern of Chinese motif described under Chinese Chippendale.

Chinese lacquer, Japanese lacquer, lacquer A hard-wearing varnish drawn from natural sources, as from the Japanese varnish tree.

Chinese lattice A combination of horizontal, vertical, and diagonal lines, slats, or bars, that form a geometric pattern, as in Chinese Chippendale.

Chinese white A paint using zinc oxide as the principal pigment.

chink In a wall, a crack or fissure of greater length than breadth.

chinking The material used to fill chinks (i.e., long cracks, openings, or fissures), especially between logs that form the exterior walls of log cabin construction. Where the cracks are small, the filling material is often mud or plaster; where the cracks are large, the filling may include wood chips, pebbles, straw, or small sticks.

chinking board A board used to cover chinking in an exterior wall.

chinoiserie A Western European and English architectural and decorative fashion employing Chinese ornamentation and structural elements, particularly in 18th cent. Rococo design.

chip A broken fragment of marble or other mineral aggregate, screened to a specified size.

chip ax A small ax for chipping timber or stone into shape.

chipboard See particleboard.

chip carving Hand-decorating a wood surface by slicing away chips, forming incised geometric patterns.

chip cracks, eggshelling Same as checking except that the edges of the cracks are raised or pulled away from the plaster base, resulting in the loss of bond.

chip concrete Concrete which uses broken stones as an aggregate, 1; provides greater bending and splitting tensile strength than concrete which has gravel as an aggregate because of the rougher surfaces of the broken stones.

chipped glass See chunk glass.

chipped grain A wood surface from which small bits have been ripped as a result of defective planing or machine work.

chipper See paving breaker.

chipper chain saw A chain saw whose cutting teeth are shaped so as to permit curved cuts.

chipping Treatment of a hardened concrete surface by chiseling.

chipping resistance Of a paint coating (or the like), the ability of one or more coats to resist the removal of any portion of its surface as a result of impacts.

chisel A hand tool with a cutting edge on one end of a metal blade (usually steel); used in dressing, shaping, or working wood, stone, metal, etc.; usually driven with a hammer or mallet. Also see cold chisel and wood chisel.

chisel bar A heavy, steel hand bar with a chisel edge on one end.

chisel chain saw A chain saw whose cutting teeth are shaped so that it can only make straight cuts.

chisel knife A knife with a square edge, usually 1½ in. (3.8 cm) or less in width, used to scrape off paint or wallpaper in areas where a wider-edged stripping knife would not be suitable.

chisel pattern A pattern of shingles or tiles on a roof in which the bottom corners of the shingles or tiles are clipped at an angle.

chlorinated paraffin wax A viscous liquid or solid used as a plasticizer or in flame-retardant paints.

chlorinated polyethylene A synthetic material that is widely used as a roofing material.

chlorinated polyvinyl chloride (PVC) A plastic, widely used for piping in both hot- and cold-water systems and in drainage systems— especially where corrosion may be a problem.

chlorinated rubber A white powder containing 67% rubber by weight, produced by the reaction of chlorine and rubber; used in plastics, adhesives, and corrosion- and acid-resistant paints.

chock A wedge or block used to prevent an object from moving.

choir That part of a church, between the sanctuary and the nave, usually occupied by a group of singers.

choir aisle An aisle parallel to and adjoining the choir.

choir loft A balcony choir area.

choir rail A railing separating the choir from the nave or the crossing.

choir screen, choir enclosure A screen wall, railing, or partition of any type dividing the choir from the nave, aisles, and crossing.

choir stall A seat with arms and a high back, often covered with a canopy, for clergy and singers.

choir wall A wall between piers and under an arcade screening the choir from the aisles.

choltry Same as choultry.

chomper Same as split-face machine.

choneion In the Greek Orthodox church, a piscina.

chopping block See butcher block.

choragic monument In ancient Greece, a commemorative structure, erected by the successful leader in the competitive choral dances in a Dionysiac festival, upon which was displayed the bronze tripod received as a prize; such monuments sometimes were further ornamented by renowned artists.

choragium In ancient Greece and Rome, a large space behind a theater stage where the chorus rehearsed and where stage properties were kept.

choraula Rehearsal room in a church for a choir.

chord 1. A principal member of a truss which extends from one end to the other, primarily to resist bending; usually one of a pair of such members. 2. The straight line between two points on a curve. 3. The span of an arch.

chord modulus See modulus of elasticity.

choultry 1. A caravansary. 2. In India, a large village hall or place of assembly.

chrismatory A niche close to a church font which holds the consecrated oil for baptism.

chrismon Christ symbol composed of the first two letters of the Greek word for Christ, chi and rho; a “Christogram.”

Christian door In Colonial New England, the paneled front door of a house in which the stiles and rails of the door form a pattern suggestive of a cross, the two lower stiles and rails form a pattern vaguely suggestive of an open book, representing the Bible. Also called a cross-and-bible door.

Christogram See chrismon.

chromate To coat a metal surface with a rust-inhibiting primer of lead or zinc chromate.

chromaticity The color quality of light definable by its dominant (or complementary) wavelength and its purity, taken together.

chrome green 1. A green pigment made by blending lead chromate yellow and iron blue pigments. 2. Chromium oxide.

chrome steel A very hard wear-resistant steel having a high elastic limit; usually contains 2% chromium and from 0.8 to 2% carbon.

chrome yellow, Leipzig yellow A family of inorganic yellow pigments, principally lead chromate, but blended with lead sulfate or other lead salts to produce a range of yellow-to-orange pigments.

chromium A hard, brittle metal resistant to corrosion, workable when annealed, gray-white in color; used in alloys, esp. steel, and in plating.

chromium oxide A durable green pigment having good alkali resistance; rather expensive and sparingly used.

chromium plating A plating with chromium used to provide a protective finish which is extremely resistant to corrosion and a surface of extreme hardness; used for decorative purposes because of the smooth surface and ability to take a high polish.

chromium steel Same as chrome steel.

chronic-disease hospital An institution which provides facilities and services primarily for chronically ill patients who require long-term care.

chryselephantine Made of gold and ivory; descriptive of statues of divinities, like Zeus at Olympia, with ivory for the flesh and gold for the drapery, on a wooden armature.

CHU Abbr. for centigrade heat unit.

chuck A device with adjustable jaws used for centering and holding a cutting bit, drill bit, etc.

chuff brick See salmon brick.

chunk glass A piece of glass of unusual thickness; many times thicker than ordinary glass.

church An edifice or place of assemblage specifically set apart for Christian worship.

church house A building used for the social and secular activities of a parish.

church stile Old English for pulpit.

churn drill A drill whose cutting action is achieved by raising and dropping a chisel bit.

churn molding Same as zigzag molding.

Churrigueresque style A Spanish decorative style, often used in the late 17th century and the first half of the 18th century, characterized by elaborate and lavish Baroque ornamentation and detailing; named after the Spanish architect José Churriguera (1655–1725); also see Mission architecture, Plateresque architecture, Spanish Colonial architecture.

chute An open-top trough through which bulk materials are conveyed and lowered by gravity.

chymol Same as gemel.

CI On drawings, abbr. for cast iron.

ciborium A baldachin.

CIB Abb. for “International Council for Building Research Studies and Documentation,” Rotterdam, the Netherlands.

CIBS Abbr. for “Chartered Institution of Building Services.”

CIE Abbr. for “Commission Internationale de l’Eclairage” (International Commission on Illumination).

cif Abbr. for “cost, insurance, and freight.”

cilery The ornamental carving, such as foliage, around the capital of a column.

cill British term for sill.

cillery Same as cilery.

cill-wall A low, narrow, masonry wall that supports a timber-framed structure; keeps the lowest beam (i.e., the cill-beam) dry, and thus prevents it from rotting.

cima See cyma.

cimbia A band or fillet around the shaft of a column.

cimborio A lantern or cupola above or nearly above the high altar in Spanish architecture.

cimeliarch The treasury of a church for storing valuables such as ceremonial garb and holy objects.

cinch See lead pipe cinch.

cincture, girdle A ring of moldings around the top or bottom of the shaft of a column, separating the shaft from the capital or base; a fillet around a post. Also see necking.

cinder block, Brit. clinker block A lightweight masonry unit made of cinder concrete; widely used for interior partitions.

cinder concrete A lightweight concrete made with cinders as the coarse aggregate.

cinders 1. Blast-furnace slag or similar material from volcanoes. 2. Ashes, esp. from soft coal.

cinerarium A depository for urns containing the ashes of the dead.

Cinquecento architecture Renaissance architecture of the 16th cent. in Italy.

cinquefoil A five-lobed pattern divided by cusps; also see foil.

cinquefoil arch A cusped arch having five foliations worked on the intrados.

CIOB Abbr. for “Chartered Institute of Building.”

CIP Abbr. for “cast-iron pipe.”

cippus A small pillar for commemorative inscriptions, boundary markers, gravestones, etc.

CIR 1. On drawings, abbr. for “circle” or “circular.” 2. On drawings, abbr. for “circuit.”

CIR BKR On drawings, abbr. for circuit breaker.

CIRC On drawings, abbr. for “circumference.”

circle end A starting step having the shape of a half circle.

circle-on-circle face See circular-circular face.

circle trowel A trowel having a concave or convex blade; used in plastering curved surfaces.

circline lamp A fluorescent lamp tube bent in the form of a circle; the entire lamp forms a toroid.

circuit 1. A continuous electrical path, or a system of conductors, through which an electric current is intended to flow. 2. An assembly of pipes and fittings, forming part of a hot-water system, through which water circulates.

circuit breaker An electric device for opening and closing a circuit, designed to open the circuit automatically upon flow of a predetermined value of abnormally high current; may be repeatedly reclosed and reused as an automatic over-current protection device without replacement of any components.

circuit controller Any type of device used to close and/or open an electrical circuit.

circuit main See main, 1.

circuit vent In plumbing, a branch vent which serves two or more traps and extends from in front of the last fixture connection of a horizontal branch to the vent stack.

circular arch An arch whose intrados takes the form of a segment of a circle.

circular barn A barn having a circular plan; requires less building material than a rectangular barn enclosing the same volume, but usually costs somewhat more to construct. Also called a cylindrical barn or a round barn.

circular-circular face, circle-on-circle face In stonework, carpentry, and joinery: a face worked to convex spherical shape, presenting a curved outline in both plan and elevation.

circular-circular sunk face, circle-on-circle sunk face Same as circular-circular face but presenting a concave outline, in both plan and section.

circular cutting and waste A measure of the excess tiling, flooring, roofing material, etc., that must be discarded when a curved floor or roof is laid.

circular face In stonework, a face worked to convex circular shape.

circular mil-foot A unit electric conductor having a cross-sectional area of 1 circular mil and a length of 1 ft.

circular mill The area of a circle having a diameter of 1 mil (

in.); used in specifying wire size; equals an area of 0.00051 sq mm.

circular miter The miter formed by the intersection of a curved and a straight piece.

circular plane Same as compass plane.

circular saw A power-operated saw in the form of a circular steel blade with teeth along the perimeter. Also see table saw.

circular spike A type of metal timber connector having a series of sharp teeth in a circle; the teeth dig into the wood as a bolt is tightened, thereby preventing lateral motion.

circular stair Same as spiral stair; a stair having a cylindrical staircase.

circular sunk face In stonework, a face worked to concave circular shape; the opposite of circular face.

circular window A large window having the shape of a full circle; often has decorative elements within the circle disposed in a radial manner.

circular work See compass work.

circulating head, circulating pressure A measure of the pressure available in a hot-water supply system for circulating water around the convection circuit.

circulating water system A system in which the same water circulates around a closed loop; sometimes a small amount must be added to make up for losses.

circulation 1. The traffic pattern through an area or building. 2. In a building, a scheme providing for a smooth, economical, and functional flow of traffic. 3. A means of travel through a building, such as doors, corridors, stairs, and elevators. 4. The continuous flow of a liquid or gas within a closed circuit.

circulation area See primary circulation area.

circulation path Same as circulation, 3.

circulation pipe A pipe forming part of the primary or secondary circuit of a hot-water system.

circulation-type hot-water supply system A supply system which circulates water through a storage tank and one or more gas-fired heaters by means of a pump; circulation improves the transfer of heat and the temperature distribution within the system.

circumvallate To surround an area with a wall or ramparts.

circumvolution One of the turns in the spiral of the volute of an Ionic capital.

circus, hippodrome In ancient Rome, a roofless enclosure for chariot or horse racing and for gladiatorial shows; usually a long oblong with one rounded end and a barrier down the center; seats for the spectators usually on both sides and around one end.

CIRIA Abbr. for “Construction Industry Research and Information Association in Britain.”

cissing, sissing 1. A slight shrinkage of a glossy paint coat resulting in small cracks through which the undercoat may be seen; a mild form of crawling, 2. 2. A process for preparing a wood surface for graining by wetting with a sponge.

cist Same as cistvaen.

cistern An artificial reservoir or tank for storing water at atmospheric pressure (such as rainwater collected from a roof) for use when required.

cistern head Same as leader head.

cistvaen, kistvaen A Celtic sepulchral chamber of flat stones set together like a box, and covered by a tumulus.

citadel A fortress or castle in or near a city, intended to keep the inhabitants in subjugation, or, in case of a siege, to supply a final refuge.

city plan A large-scale, comprehensive map of a city delineating streets, important buildings, and other urban features compatible with the scale of the map.

city planning, town planning, urban planning Planning a future community, or the guidance and shaping of the expansion of a present community, in an organized manner and with an organized layout, taking into account such considerations as convenience for its inhabitants, environmental conditions, social requirements, recreational facilities, esthetic design, and economic feasibility; includes a study of present requirements and conditions, as well as projections for the future; such planning usually includes proposals for its implementation. See community planning.

civery See severy.

civic center An area of a city where municipal buildings are grouped; esp. includes the city hall, court house(s), public library, and other public buildings such as a municipal auditorium, art gallery, etc.

civic crown, civic wreath In ancient Rome, an honorary ornament, consisting of a garland of oak leaves, on a monument to one who had saved the life of a Roman citizen in battle.

civil engineer An engineer trained in the design of static structures such as buildings, roads, tunnels, and bridges and the control of water and its contaminants.

City Beautiful movement A movement in the US, principally from about 1890 to the 1920s, which advocated the beautification of cities.

CKT On drawings, abbr. for “circuit.”

CKT BKR On drawings, abbr. for circuit breaker.

CL Abbr. for center line.

C-labeled door A door carrying a certification from the Underwriters’ Laboratories, Inc. that it meets the requirements for a class-C door.

clachan A small village or hamlet in Scotland or Ireland.

clack valve A type of check valve in which the controlling element is hinged on one edge, opening for flow in one direction and closing when the flow is reversed.

clad Said of a surface that is surface sheathed.

clad alloy An alloy having metallurgically bonded surface coating; applied as corrosion protection, for surface appearance, for use in brazing, etc.

clad brazing sheet A metal sheet which is clad, on one or both sides, with a brazing filler metal.

cladding 1. See siding. 2. A metal coating which is bonded to another metal; see clad alloy. 3. In welding, the deposition of filler metal on a metal surface to obtain desired properties or dimensions; also called surfacing. 4. A nonstructural material (or the surface formed by such a material) used as the exterior covering for the carcass or framework of a building. 5. The surface on which shingles, tiles, or clapboards are fastened. Also see siding and veneer.

cladding rail Same as girt.

clairecolle See clearcole.

clairvoyée, claire-voie An ironwork screen, openwork fence, gate, or grille through which a vista can be enjoyed.

clam The bucket of a clamshell.

clamp A wood and/or metal device designed to hold components firmly, esp. during gluing, machining, soldering, welding, etc.

clamp brick A stock brick which has been held in a clamp while being burned in a kiln.

clamping plate A metal connector which is bolted to a joint of a wooden frame to strengthen it; a type of timber connector.

clamping screw See screw clamp.

clamping time The period of time a glued joint must be tightly held during curing.

clamp nail A specialized fastener used to pull and to hold mitered joints together.

clamshell 1. A wood molding, the profile of which resembles that of a clamshell. 2. A bucket used on a crane or derrick for handling granular materials. Its jaw-like halves close and open by cable or hydraulic action.

clapboard, bevel siding, lap siding A wood siding commonly used as an exterior covering on a building of frame construction; applied horizontally and overlapped, with the grain running lengthwise; thicker along the lower edge than along the upper.

clapboard gauge, siding gauge A device used to space clapboards so that they are applied parallel to each other.

clapboard house A term occasionally used as a synonym for Virginia house.

clapper In fire sprinkler systems, a type of sealing assembly.

clapper valve Same as clack valve.

clapping stile Same as lock stile.

clarification drawing A graphic interpretation of the drawings or other contract documents issued by the architect as part of an addendum, modification, change order, or field order.

Clarke beam A type of built-up wood beam consisting of joists or planks which are bolted together and then reinforced with wood pieces nailed along both edges of the joint.

clasp nail Same as cut nail.

clasping buttress A buttress that wraps around the corner of a building.

class As applied to concrete: a characterization according to some quality (such as compressive strength) or usage.

class A, B, C, D, E, F A classification applied to fire doors, fire windows, roof coverings, interior finishes, places of assembly, etc., to indicate gradations of fire safety. See fire-endurance, fire-door rating.

class-A door A door having a 3-hr fire-endurance rating, suitable for use as a closure in a class-A opening.

class-B door A door having a 1- or 1½-hr fire-endurance rating, suitable for use as a closure in a class-B opening, such as fire exits and passageways.

class-C door A door having a ¾-hr fire-endurance rating, suitable for use as a closure in a class-C opening.

class-D door A door having a 1½-hr fire-endurance rating, suitable for use as a closure in a class-D opening in an exterior wall.

class-E door A door having a ¾-hr fire-endurance rating, suitable for use as a closure in a class-E opening in an exterior wall.

Classical architecture The architecture of Hellenic Greece and Imperial Rome on which the Italian Renaissance and subsequent styles such as the Baroque and the Classic Revival based their development. The Five Orders are a characteristic feature. See illustrations under order.

Classical order See order.

Classical Revival style An architectural style, used in many major public buildings from about 1770 to 1830 and beyond; typified by simplicity, dignity, monumentality, and purity of design; based primarily on the use of Roman forms of classical antiquity, although later examples exhibit some characteristics of the Greek Revival style which followed. Sometimes called Early Classical Revival, Jeffersonian Classicism, Neoclassical Revival, or Roman Classicism. Buildings in this style were usually rectangular in plan, two rooms deep, gable-fronted, with the long side of the house commonly facing the street; they commonly exhibit many of the following attributes: a symmetrical form sometimes similar to a classicaltemple; two stories high, often with one- or two-story wings; walls of brick, stucco, stone, or wood construction; typically, a two-story monumental portico, painted white, with a triangular pediment, frequently with a semicircular window set within its tympanum; a pedimented roof, usually supported by four columns on square bases; an entablature above the columns; a low hipped roof, occasionally partially hidden by balustrades; usually five-ranked; a paneled door beneath a semicircular or elliptical fanlight. Classical Revival architecture reemerged in popularity from about 1895 to 1940, with modifications, as described under Neoclassical style.

classic box A Colonial revival house having a hipped roof and a full-width front porch.

classicism In architecture, principles that emphasize the correct use not only of Roman and Greek, but also of Italian Renaissance models.

Classic Revival A term often used as a synonym for the Classical Revival style.

classified excavation An excavation in which there are separate prices for common excavation and for rock excavation; compare with unclassified excavation.

class P ballast See ballast.

classroom window A window which is twice as wide as an ordinary window, usually having two or more side-by-side hopper lights and a single fixed light above them.

clathri A lattice of bars, as of cages for animals or gratings for windows.

clause In the AIA documents, a subdivision of a subparagraph, identified by four numerals, e.g., 3.3.10.1.

claustral, cloistral Pertaining to a cloister.

clavel, clavis A keystone of an arch.

clavis See clavel.

claw bar See pinch bar.

claw chisel A chisel with a serrated cutting edge; used in cutting stone.

claw hammer A carpenter’s hammer with a flat striking face; the other end of the head is curved, and divided into two claws for pulling nails.

claw hatchet See shingling hatchet.

claw plate A timber connector which is round in shape.

clay A fine-grained, cohesive, natural earthy material; plastic when sufficiently wet; rigid when dried; vitrified when heated in a kiln to a sufficiently high temperature; used in making brick, as wall infilling, and as daub in wattle-and-daub.

clay-and-hair mortar A plastic mixture of clay and water to which animal hair is added to improve the mechanical strength of the resulting mortar after it has dried.

clay-and-sticks chimney A chimney constructed of clay or mud and sticks, and then coated on the interior with clay, mud, or plaster to provide some protection against setting the chimney on fire; used in homes in many frontier areas where bricks, stones, and lime mortar were not available.

clay binder See binder soil.

clay brick A solid masonry unit made of clay, usually formed into a rectangular unit while in the plastic state and treated in a kiln at an elevated temperature to harden it.

clay cable cover A fired-clay covering for underground electric cables.

clay content Of a heterogeneous material such as soil or a natural concrete aggregate, the percentage of clay by weight.

clay masonry unit A building unit, larger than a brick, composed of burnt clay, shale, fire clay, or some mixture thereof.

clay-mortar mix Masonry mortar which has been plasticized by the addition of finely ground clay.

clay pipe See vitrified-clay pipe.

clay puddle See puddle.

clay size That portion of fine-grained soil that is finer than 0.002 millimeter.

clay spade An attachment for a pneumatic paving breaker, with a wide, flat chisel-like working blade that cuts through cohesive material like clay.

clay tile 1. A roofing tile of hard, burnt clay. 2. In flooring, a quarry tile.

cleading The boards lining the sides of an excavation, pit, or shaft.

cleanability The property of a paint film which permits easy removal of dirt, stains, and other surface contamination.

clean agent In a fire suppression system, any electrically nonconducting, volatile, or gaseous extinguishant that does not leave a residue when it evaporates.

clean aggregate Fine or coarse aggregate, free of such material as clay, silt, or organic substances.

clean back In masonry, the visible end of a stone laid as a bondstone.

cleaning eye A cleanout.

cleaning sash, cleaning ventilator The movable part of a window which opens only for cleaning the window; usually unlocked with a special key or wrench.

cleanout 1. A pipe fitting with a removable plug which provides access for inspection or cleaning of the pipe run. Also called an access eye or cleaning eye. 2. An opening at the base of a chimney, stack, or breeching for the removal of dust, soot, etc. 3. An opening in concrete forms for removing debris; closed before the concrete is placed.

cleanout door 1. An ashpit door. 2. A door providing access to a soil pipe, the base of a column form, or the like. 3. A soot door.

clean power Electric power having a relative absence of electrical noise and harmonics so that its voltage waveform is essentially a sine wave.

clean room An assembly room for precision products whose quality would be affected by dust, lint, or airborne pathogens; usually has smooth room surfaces to prevent dust collection; air precipitators or filters keep dust, lint, etc., to a specified minimum level.

clean stuff Same as clear lumber.

clean timber British term for clear lumber.

clear The net distance, free from interruption, between any two surfaces or areas.

clearage Same as clearance.

clearance 1. Open space between two elements of a building to aid in proper placement, to compensate for minor inaccuracies in cutting, or to allow unobstructed movement between parts. 2. The space or distance allowed for anchorage or erection processes or to accommodate dimensional variations in the building structure. 3. See door clearance.

clear ceramic glaze Said of an inseparable ceramic glaze that is firebonded and translucent or tinted with a lustrous finish.

clearcole, clairecolle 1. A primer consisting of glue, water, and white lead or whiting. 2. A clear coating used in application of gold leaf.

clear dimension The open space between two components or members of a building.

clear floor space According to the Americans with Disabilities Act, the minimum unobstructed floor space needed to accommodate a wheelchair and its occupant.

clear glaze A colorless or colored transparent ceramic glaze. Also see ceramic color glaze.

clear height A vertical height providing an unobstructed clearance, 1.

clearing The cutting down of bushes and trees and the digging and removal of their roots and stumps.

clearing arm A branch provided on a drain to facilitate the clearing of obstructions with a drain rod.

clear lumber, clean timber, clears, clear stuff, clear timber, free stuff Wood free of knots and other defects.

clear span The distance between the two inside faces of the supports of a span.

clearstory Same as clerestory window.

cleat A small block or strip of wood nailed on a member or on a surface; used to support a brace or to hold a member or object in place temporarily.

cleat wiring Electric wiring on cleats or insulated supports which are mounted on a wall or other surface, leaving the wiring exposed; conduits or raceways are not used.

cleavage 1. In rocks, a tendency to split along parallel, generally closely spaced surfaces as, for example, in slate. 2. In some stone industries, the splitting along the depositional layering. 3. The rupturing of adhesive bonds between rigid materials; a prying action. 4. A tendency in some woods to split along closely spaced parallel planes, as in shingles.

cleavage plane In a crystalline material, such as certain types of rocks, a plane along which splitting takes place most easily.

cleave board Same as rived board.

cleft finish Said of a stone that has good cleavage, 2 along parallel planes; for example, slate.

cleft timber Timber which has been split along the grain to approximate dimensions.

cleithral Same as clithral.

clench See clinch.

clench bolt See clinch bolt.

clenching, clench nailing The hammering over of the point of a nail against a wood face to secure its adhesion under rough usage.

clench nail See clinch nail.

clerestory, clerestory window 1. An upper zone of wall pierced with windows that admit light to the center of a lofty room. 2. A window so placed. (See illustration p. 218.)

clerk of the works The owner’s site representative or owner’s inspector at a construction site.

clevis An iron (or a link in a chain) bent into the form of a horseshoe, stirrup, or letter U, with holes in the ends to receive a bolt or pin. (See illustration p. 218.)

CLG On drawings, abbr. for ceiling.

climbing crane A hoisting device used in the erection of high-rise buildings; a vertical mast is fastened to structural members of the building framework and is moved up as the structure rises during construction; a horizontal boom, equipped with a winch and hoist line, is swung from the top of the vertical mast.

climbing form A concrete form which is raised vertically for succeeding lifts, 6 of concrete in a given structure, usually supported on anchor bolts or rods embedded in the top of the previous lift; the form is moved only after an entire lift is placed and partially hardened; not the same as a slip form, which moves during the placement of concrete.

clinch, clench To secure or fasten a nail, staple, screw, etc., by hammering the protruding point so that it is bent over.

clinch bolt, clench bolt A bolt with one end designed to be bent over, to prevent withdrawal.

clinching See clenching.

clinch joint Same as lap joint, 2 secured with clinch nails.

clinch nail, clench nail Any nail designed for clinching after driving.

clinic 1. A facility, independent or part of a hospital, in which ambulatory patients receive diagnostic and therapeutic medical and surgical care. 2. Single-focus or general-purpose units of the entire facility, such as the cardiac clinic or the pediatric clinic.

clink 1. A short pointed steel bar; used, by striking with a sledgehammer, to break up pavement or road surfaces. 2. One of many small cracks in steel due to differential expansion in heating. 3. A sealed edge between adjacent sheets of flexible-metal roofing material.

clinker 1. A partially fused product of a kiln, which is ground for use in cement; also called cement clinker. 2. A vitrified or partially vitrified residue of coal which has been burnt in a furnace; used as an aggregate in cinder block. 3. A clinker brick.

clinker block British term for cinder block.

clinker brick A very hard-burnt brick whose shape is distorted, owing to nearly complete vitrification; used for paving.

clinometer An instrument for measuring vertical angles.

clip 1. A portion of a brick cut to length. 2. A special fastener made of light-gauge sheet metal or wire for the attachment of gypsum lath to channel or steel studs. 3. A small device, usually of metal, for holding larger parts in place, either by friction or by mechanical action, as a spring device of metal used to hold glass in a window.

clip angle, lug angle A short angle iron that takes a portion of the stress of any member.

clip bond A bond formed by clipping of the inside corners of facing brick laid as stretchers so as to form notches for the insertion of diagonal headers.

clip course A course of bricks that rests on a clip joint.

clipeus An ornamental disk of marble or other material, in the shape of a shield; often sculptured in relief, hung in the intercolumniations of the atria of ancient Roman dwellings.

clip joint A mortar joint which is thicker than usual; used to bring a masonry course to a required height.

clipped eaves Eaves that do not overhang the face of a wall by more than the width of the gutter.

clipped gable See jerkinhead.

clipped header, false header A half-brick placed to look like a header for purposes of establishing a brickwork pattern, as in Flemish bond.

clipped lintel A lintel which is intermittently attached to a structural member; the structural member assists the lintel in carrying the load.

clithral In early Greek architecture, having a roof that forms a complete covering; said of certain temples, as distinguished from hypaethral.

CLKG On drawings, abbr. for caulking.

CLO On drawings, abbr. for closet.

cloaca An underground conduit for drainage; a sewer, esp. in ancient Rome.

cloak rail On a closet wall, a board on which hooks are attached for hanging clothes.

cloakroom 1. A room for the deposit or checking of outer clothing. 2. A small lounge outside a legislative chamber where coats may be hung. 3. A room for checking packages or baggage, as in a theater, railway station, or airport. 4. (Brit.)A washroom and toilet.

clocher Same as belfry, 1.

clochan A type of primitive building peculiar to Ireland, usually having a beehive form, constructed of the masonry usually neither dressed nor cemented; a single stone covers the apex.

cloisonne A surface decoration in which differently colored enamels or glazes are separated by fillets applied to the design outline. For porcelain enamel, the fillets are wire secured to the metal body; for tile and pottery, the fillets are made of ceramic paste, squeezed through a small-diameter orifice.

cloister A covered walk surrounding a court, usually linking a church to other buildings of a monastery.

cloistered arch Same as coved vault.

cloistered vault A coved vault.

cloister garth The courtyard within a cloister.

cloistral See claustral.

clone One of a series of plants that is reproduced by cuttings or other vegetative methods for several generations.

close 1. An enclosed space around or at the side of a building; esp. the neighborhood of a cathedral. 2. A narrow lane leading from a street.

closed bidding Same as closed competitive selection.

close-boarded, close-sheeted 1. Covered with square-edge boards that are laid in close contact with each other, as in roofing or siding. 2. Said of fencing which is completely filled with vertical boards having no spaces between them.

close-contact glue A glue which requires very closely joined surfaces.

close couple See couple-close.

close-coupled tank and bowl A flush tank which is separate from, but attached to, a toilet bowl.

close-cut Descriptive of a hip (or valley) on a slate, shingle, or tile roof in which the pieces are cut to meet exactly on the hip (or valley).

closed building system A building system in which only its own subsystems, its own subassemblies, and its own components are interchangeable.

closed cell In a material such as foam rubber or foam plastic, one of many air spaces (cells) totally enclosed by its walls and hence not interconnecting with other cells.

closed-cell foam A cellular plastic in which the cells do not interconnect.

closed-circuit grouting Injecting grout into a hole (which intersects fissures or voids to be filled) with sufficient volume and pressure so that more grout is fed to the hole than is taken up, the excess grout being returned to the pumping plant for recirculation.

closed-circuit TV surveillance system A system comprised of a TV camera and a monitor connected by a coaxial cable; designed to provide visual surveillance; often an important adjunct to a building security system.

closed-circuit telephone A telephone on a circuit that provides telephonic communication within a limited area, such as a single building; it accepts no incoming calls from the outside nor can calls be made to the outside. Also called a house telephone or house phone.

closed competitive selection A competitive process in which the owner (or his representative) limits the lists of bidders on a building contract to those he has selected for bidding.

closed construction Said of a building component, building system, or building which is manufactured in such a way that various portions cannot be readily inspected at the installation site without their disassembly or destruction.

closed cornice 1. A boxed cornice. 2. A wood cornice which projects only slightly and has no soffit, having only a frieze board and crown molding.

closed eaves Eaves in which projecting roof members are not visible, being closed from view by boarding.

closed impeller In a pump, an impeller having two shrouds (i.e., two disks enclosing the impeller vanes). Such a pump usually requires little maintenance and usually retains its operating efficiency longer than a pump having an open impeller.

closed joint Between adjacent slabs of stone, a joint that is invisible or barely visible.

closed list of bidders See invited bidders.

closed mortise Same as blind mortise.

closed newel The central shaft of a turning stair when constructed within a continuous enclosing wall, either hollow or solid.

closed shaft A shaft roofed or enclosed at the top.

closed sheathing See closed sheeting.

closed sheeting, closed sheathing, tight sheeting A continuous frame with vertical or horizontal sheathing planks placed side by side to form a continuous retaining wall used to hold up the face of an excavation.

closed shelving In cabinets, shelving which is concealed by a door.

closed shop A construction project operating under a work system that requires membership in a particular union as a necessary condition of employment.

closed specifications Specifications stipulating the use of specific products or processes without provision for substitution.

closed stair A box stair.

closed stair string Same as close string.

closed string Same as close string.

closed string stair A stair constructed with close strings so that the treads are not visible from a side view of the stair.

closed system A heating or refrigeration piping system in which the circulating water or brine is completely enclosed and under pressure above atmospheric.

closed valley Same as concealed valley.

closed water piping system A water piping system in which a check valve or other device prevents the return of water to the water supply system.

close-grained, close-grown See narrow-ringed.

close nipple A nipple having no shoulder (i.e., no unthreaded portion) and having the shortest possible length permitted by standard practice.

closer 1. The last brick, block, stone, or tile laid in a horizontal course; may be either a complete unit or one trimmed on the site. 2. A stone course running from one windowsill to another (a variety of stringcourse). Also see king closer, queen closer.

closer mold A temporary wood form used as a guide in cutting brick to a specific size.

closer reinforcement A metal plate which is applied to a door or frame to provide additional strength for the attachment of a door closer.

closer reinforcing sleeve A plate which reinforces the rabbeted soffit and both faces of a doorframe.

close-sheeted See close-boarded.

close sheeting Same as closed sheeting.

close string, close stringer, closed stringer, curb string, housed string A staircase string whose upper edge is straight and parallel to its lower edge; the tread and riser ends are housed in the face of the string and are concealed.

close studding Construction in which the studs are placed relatively close and the intervening spaces are plastered.

closet 1. A small enclosed storage area. 2. A small private room, often off a bedroom.

closet bolt A bolt having a low circular head of extra large diameter which is cupped on the underside so that it is sealed against the surface when the bolt is tightened; used to fasten a water closet bowl to the floor.

close timbering The lining of an excavation or trench with boards having no space between them.

closet lining Red cedar boards whose odor repels moths; used to line closets.

close tolerance A tolerance closer than standard tolerance.

closet pole, closet rod A straight, round rod installed in a clothes closet to hold clothes hangers.

closet screw A long screw having a detachable head; used to fasten a water closet bowl to the floor.

closet valve The valve which controls the flushing cycle of a tank-type water closet.

close-up casement hinge A hinge similar to an extension casement hinge but having its hinge pin closer to the face of the casement, 1.

closing costs Those costs incidental to a transfer of title from seller to buyer and execution of a mortgage on a property, e.g., legal and recording fees and title insurance.

closing device, automatic closing device, self-closing device 1. A mechanism designed to ensure that an open fire door will close and latch in the event of a fire. 2. A device which ensures that a door will return to its closed position after being opened.

closing jamb Same as strike jamb.

closing ring A metal ring fastened to a door; used to pull it shut.

closing stile Same as lock stile.

closure bar Of a stair, a flat metal bar connected to the top and/or bottom surface or edge of a stringer along a wall; used to close gaps between the stringer and the wall.

closure strip A preformed asphalt or elastomeric filler strip used to close the opening in corrugated sheets at eaves, the lower edge of siding, at window beads, and the like.

clothes chute A laundry chute.

cloudiness The lack of clarity or transparency in a paint or varnish film.

clout 1. A metal plate attached to a moving wood member to protect it from abrasion. 2. A clout nail.

clout nail A nail having a large flat head, a round shank, and a long side point or duckbill point; used for fastening sheet metal, asphalt-prepared roofing, plasterboard, etc.

closure brick Same as closer, 1.

clr., Clr, Clr. In the lumber industry, abbr. for “clear.”

CLS Abbr. for “Canadian lumber sizes.”

club hammer In stoneworking, a short-handled, heavy hammer usually having a round or octagonal face.

clunch A stiff, rigid clay or a chalk, used in early British construction.

cluster development See cluster housing.

clustered column A number of columns which are grouped together and physically connected so they act as a single structural element.

clustered pier A pier, 1 composed of a number of shafts grouped together, usually around a central, more massive, shaft or core.

cluster housing Dwellings grouped closely together to form relatively compact units. The space between clusters usually is allocated to pedestrian circulation and cooperative recreational use. This pattern normally results in a higher density of land use than that of a conventional subdivision layout.

clutch A device which permits the drive train of a machine to be connected to, or disconnected from, a prime source of power; usually operates on a mechanical principle with friction surfaces that can be joined or separated, but other types include a fluid coupler.

cm Abbr. for “centimeter.”

CM Abbr. for “center matched.”

CMP On drawings, abbr. for “corrugated metal pipe.”

CMU Abbr. for concrete masonry unit.

CND On drawings, abbr. for conduit.

CNRC Abbr. for “Canadian National Research Council.”

CO 1. Abbr. for change order. 2. Abbr. for certificate of occupancy. 3. Abbr. for cleanout. 4. Abbr. for cutout.

coach bolt Same as carriage bolt.

coach house, carriage house A building or part thereof for housing carriages when not in use.

coach-mounting steps A small elevated platform on which a person would step when mounting or dismounting from a coach or carriage; often set near the entrance to a house.

coach screw See lag bolt.

coak 1. A projection from the end of a piece of wood or timber which fits into a hole in another piece to join them. 2. A dowel or hardwood pin through overlapping timbers.

coalescence The formation of a film of resinous or polymeric material when water evaporates from an emulsion or latex system, permitting contact and fusion of adjacent latex particles.

coal house A subsidiary building for the storage of coal; often connected to a blacksmith’s shop.

coal-tar felt A felt that has been saturated with refined coal-tar pitch.

coal-tar pitch, tar A dark brown to black hydrocarbon obtained by the distillation of coke-oven tar; softening point near 150°F (65°C); used in built-up roofing as a waterproofing agent.

coaming A frame or curb around an opening in a roof or floor, raised above the surrounding level to prevent the flow of water into the opening.

coarse aggregate Aggregate retained on a 4.76-mm (No. 4) sieve. Also see crushed gravel, crushed stone, gravel, pea gravel.

coarse filter In an air-conditioning system, same as prefilter.

coarse fraction That fraction of the solid particles in a soil sample having grain sizes larger than a No. 200 sieve, i.e., greater than 0.003 inch (0.075 mm) in diameter.

coarse-grained 1. See wide-ringed. 2. See coarse-textured.

coarse stuff A mixture of lime putty, hair, and sand; used as a base-coat plaster.

coarse-textured, coarse-grained, open-grained Descriptive of wood having an open, porous cell structure that usually requires filling to provide a smooth finish.

coarse-textured wood Any wood having large pores.

coat A single layer of plaster, paint, or any type of material applied to a surface.

coated bar A reinforcing bar that has been coated to increase its resistance to corrosion.

coated base sheet, coated base felt A roofing material consisting of asphalt-saturated felt which is coated with a harder viscous asphalt to increase its impermeability to moisture significantly.

coated electrode, light-coated electrode A filler-metal electrode used in arc welding which consists of a metal wire having a light coating to stabilize the arc.

coated glass Glass having a coating designed to admit light over most of the visible range but to block light in the ultraviolet and infrared ranges; the coating reflects some of heat generated within a building so that it remains in the building instead of largely being transmitted through the window, thereby effecting a saving of heat during the winter; often applied on glazing in a double window construction.

coated macadam See bitumen macadam.

coated nail An enameled nail, cement-coated nail or mechanically galvanized nail.

coating A layer of material which is applied to a surface to decorate, preserve, protect, seal, or smooth the substrate; usually applied by brushing, spraying, mopping, troweling, or dipping.

coat rack A storage rack for coats and hats; may include a boot rack, umbrella stand, and drip tray.

coatroom 1. A cloakroom. 2. A room for the deposit or checking of outer garments.

coaxial cable 1. A cable consisting of two concentric conductors (an inner conductor and an outer conductor) insulated from each other by a dielectric; commonly used for the transmission of high-speed electronic data and/or video signals. 2. A single transmission cable having a concentric conductor and shielding; used for communications transmission, such as for television signals.

cob A mixture of straw, gravel, and unburnt clay; used esp. for walls.

cobble, cobblestone 1. A rock fragment between 2½ and 10 in. (64 and 256 mm) in diameter, used for rough paving, walls, and foundations. 2. Coarse aggregate for concrete, having a nominal size in the range 3 to 6 in. (75 to 150 mm).

cobblestone house A house whose rubblework walls are surfaced with cobblestone.

cob wall A wall formed of unburnt clay mixed with chopped straw, gravel, and occasionally with layers of long straw, in which the straw acts as a bond.

cobwebbing Formation of strands, resembling cobwebs, of dried or semidried paint when expelled from a spray gun; usually caused by highly polymerized binders.

cochlea 1. A tower for a spiral staircase. 2. A spiral stair.

cochleary, cochleated Spirally or helically twisted, as a spiral stair.

cocina In Spanish architecture, a kitchen.

cock 1. See faucet. 2. A stopcock.

cock bead A bead which is not flush with the adjoining surface but is raised above it.

cocking 1. Same as cogging. 2. Tipping sideways.

cocking piece See sprocket.

cockle-shell cupboard Same as shell-headed cupboard.

cockle stair A spiral stair.

cockloft A garret under a roof, above the highest ceiling. Also see loft, 2.

cockscomb A drag.

cockspur fastener A fastener on a casement window.

coctile Made by baking, as porcelain or a brick.

coctilis Said of an ancient Roman building constructed of brick hardened in a kiln, as opposed to brick hardened in the sun.

code 1. A legal instrument adopted within a political jurisdiction (such as a town, county, state, province, parish, etc.) that prescribes the minimum acceptable levels of the design, construction, installation, and performance of materials, components, devices, items of equipment, appliances used in a building, or building systems and/or subsystems. 2. A published body of rules and regulations for building practices, materials, and installations, designed to protect the health, welfare, and safety of the public, such as a building code, health code, etc. Codes established by municipal, state, or federal authorities usually have the power of law.