Z

zaguán 1.In Spanish architecture and derivatives, an entry; often a massive wooden gate that was often sheltered and wide enough to permit large wagons or coaches to enter the courtyard (placita) of a casa del rancho. Often had a small door adjacent to, or a door set within the zaguán, for pedestrian traffic. 2. In ecclesiastical Hispanic architecture, a corridor between a cloister and its exterior.

zambullo door In early Spanish Colonial architecture, especially in New Mexico, a wood door hung on wood pintle hinges.

zapata In Spanish Colonial architecture of the Americas, a horizontal piece of wood, atop a post, that provides greater bearing area to support the load imposed on the post from above; usually carved; similar to a bolster, 1 but often more highly decorative.

Zapotec architecture An eclectic architecture of Mesoamerica, especially in Oaxaca, Mexico. Characterized by multiterraced pyramids ascended by broad stairways, accented by wide balustrades and tablets, the use of circular supporting columns, and free-standing structures placed around a large plaza.

zax Same as sax.

Z-bar In a suspended acoustical ceiling, one form of main runner.

Z-braced battened door A battened door held together by two horizontal boards that are joined by a diagonal board; suggestive of the letter Z.

zebrawood, zebrano A moderately hard and heavy wood, pale yellow or pinkish brown, having pronounced dark stripes; found in central and western Africa. Used for plywood and decorative applications.

zee A metal member having a modified Z-shaped cross section; the internal angles of the Z are approximately equal to right angles.

zeolite A coarse-grained chemical compound used in water-softening equipment; consists of a greenish granular material containing iron (up to 25%), a large percentage of silica, and some alumina and potash.

zeolite softening A water softening process now called cation-exchange softening.

zero-slump concrete Said of freshly-mixed concrete which has no measurable slump; compare with no-slump concrete.

zeta 1. A closed or small chamber. 2. A room over a porch of an early Christian church, where the porter or sexton lived and where documents were kept.

ziggurat A Mesopotamian temple tower; from the end of the 3rd millennium B.C. on, ziggurats rose in three to seven stages, diminishing in area and often in height square (Sumer) or rectangular (Assyria), built of mud brick and faced with baked brick laid in bitumen.

zigzag, dancette An ornamental molding of continued chevrons.

zigzag bond Same as or similar to herringbone bond.

zigzag fence A fence constructed of split rails that (in plan) alternate in direction, usually at a wide angle of about 120 degrees. At the intersection between the two stacks of rails, uprights are sometimes driven in the ground and lashed to the fence to improve its stability.

Zigzag Moderne See Art Moderne.

zigzag molding, dancette An ornamental molding of continued chevrons. Also see reversed zigzag molding.

zigzag riveting Same as staggered riveting.

zigzag rule A folding rule whose sections are pivoted; stiff when fully opened.

zinc A hard bluish white metal, brittle at normal temperatures, very malleable and ductile when heated; not subject to corrosion; used for galvanizing sheet steel and iron, in various metal alloys, and as an oxide for white paint pigment.

zinc chromate, buttercup yellow, zinc yellow A bright yellow stable pigment used in paints, esp. in metal primers as a rust-inhibiting pigment.

zinc coating See galvanizing.

zinc dust A fine gray powder of zinc metal usually of at least 97% purity; used as a pigment in paint primer for galvanized iron and other metal substrates.

zinc oxide, zinc white A white water-insoluble pigment which has low hiding power; used in paints to provide durability, color retention, and hardness, and to increase sag resistance.

zinc white See zinc oxide.

zinc yellow See zinc chromate.

zocco Same as socle.

zone 1. In an air-conditioning or heating system, a space (or group of spaces), served by the system, whose temperature (or humidity) is regulated by a single control. 2. A vertical or horizontal subdivision of a water supply system, sprinkler system, or standpipe system. 3. See pressure zone.

zoned heating Heating or cooling in one area of a building which is completely independent of the control of the heating in other areas of the building.

zone of saturation The level below which the subsoil and rock masses of the earth are fully saturated. See illustration under groundwater.

zoning The control by a municipality of the use of land and buildings, the height and bulk of buildings, the density of population, the relation of a lot’s building coverage to open space, the size and location of yards and setbacks, and the provision of any ancillary facilities such as parking. Zoning, established through the adoption of a municipal ordinance, is a principal instrument in implementing a master plan.

zoning ordinance A regulation that governs the location and use of land and buildings in a specific area.

zoning permit A permit, issued by the appropriate governing agency, which authorizes land to be used for specific purposes.

zoological garden A park, often quite large, designed for exhibiting wild animals.

zoomorph An image or symbol of some representation of an animal.

zoophoric column A column bearing a figure or figures of one or more men or animals.

zoophorus A horizontal band bearing carved figures of animals or persons, esp. the Ionic frieze when sculptured.

zotheca In Near Eastern architecture and derivatives, an alcove off a living room.