Glossary

American National Standards Institute (ANSI) — A standards-making organization that rates tile for water permeability.

Art tiles — Hand-finished tiles with designs, pictures, or patterns. Art tiles are often used to accent a large tile layout.

Back buttering — Spreading mortar on the back of a tile before pressing it onto the substrate.

Baseboard tile — Baseboard-shaped tiles used to replace wood baseboards.

Bullnose trim tile — Tile with one rounded edge that is meant to be left exposed.

Cement body tile — Tile made from concrete poured into forms.

Coefficient of friction — The measure of a tile’s slip resistance. Tiles with high numbers are more slip resistant.

Decorative tile — Tile with designs, pictures, or relief. Decorative tiles are generally used as accents in a field of solid-color tiles.

Dry fit — Installing tile without mortar in order to test the layout.

Expansion joint — A joint in a tile layout filled with a flexible material such as caulk instead of grout. The expansion joint allows the tile to shift without cracking.

Field tiles — The main tile in a tile design. As opposed to trim or accent tiles.

Floor tile — Any type of tile designated for use on floors. It can generally also be used for walls or countertops.

Floor-warming systems — A system of heating elements installed directly under the floor material. Floor-warming systems are intended to provide supplemental radiant heat for a room.

Glass tile — Tile made of glass. Glass tile is often used as accent tile.

Glazed ceramic — Tile made from refined clay that has been coated with a glaze and then fired in a kiln.

Grade — Ratings applied to some tile indicating the quality and consistency of manufacturing. Grade 1 tile is standard, suitable for most applications; grade 2 may have minor glaze and size imperfections; grade 3 tile is thin and suitable only for wall or decorative applications.

Grout — A dry powder, usually cement based, that is mixed with water and pressed into the joints between tiles. Grout also comes with latex or acrylic added for greater adhesion and impermeability.

Impervious — Tile that absorbs less than .5% of its weight in water.

Isolation membrane — A flexible material installed in sheets or troweled onto an unstable or damaged base floor, subfloor, or wall before installing tile. The isolation membrane prevents shifts in the base from damaging the tile above.

Joists — The framing members that support the floor.

Kiln — A high-temperature oven used to harden clay tile.

Liners — Narrow tiles used for adding contrasting lines to tile layouts.

Listello — A border tile, usually with a raised design. Also called listel.

Mastic or organic mastic — A type of glue for installing tile. It comes premixed and cures as it dries. It is convenient for wall tiles smaller than 6 × 6, but it is not suitable for floors.

Metal tile — Tile made of iron, stainless steel, copper, or brass. Metal tile is often used as accent tile.

Mortar or thin-set mortar — A mixture of Portland cement and sand and occasionally a latex or acrylic additive to improve adhesion.

Mosaic tile — Small colored tiles used to make patterns or pictures on walls and floors.

Natural stone tile — Tile cut from marble, slate, granite, or other natural stone.

Non-vitreous — Very permeable tile. Non-vitreous tile absorbs more than 7% of its total weight in water. Not suitable for outdoor installations.

Porcelain Enamel Institute (PEI) — A tile industry group that issues ratings on tile’s resistance to wear.

Porcelain tile — Tile made from refined white clay fired at high temperatures. Porcelain is usually dyed rather than glazed, and thus its color runs the tile’s full thickness.

Quarry tile — Tile formed to look like quarried stone.

Reference lines — Lines marked on the substrate to guide the placement of the first row of tile.

Saltillo — Terra-cotta tile from Mexico. Saltillos have a distinctly rustic appearance.

Sealants — Sealants protect non- and semi-vitreous tile from stains and from water damage. Sealants are also important for protecting grout.

Self-spacing tile — Tile with attached tabs for maintaining even spacing.

Semi-vitreous — Moderately permeable tile. Absorbs 3 to 7% of its total weight in water. Not suitable for outdoor installations.

Spacers — Plastic lugs meant to be inserted between tiles to help maintain uniform spacing during installation.

Story stick — A length of 1 × 2 lumber marked with the tile spacing for a specific layout.

Subfloor — The surface, usually made of plywood, attached to the floor joists.

Substrates or underlayment — A surface installed on top of an existing floor, subfloor, or wall. The substrate creates a suitable surface for installing tile. Substrate materials include cementboard, plywood, cork, backerboard, greenboard, or water-proofing membrane.

Terra-cotta tile — Tile made from unrefined clay. Terra cotta is fired at low temperature. Its color varies greatly depending on the source of the clay.

Trim tile — Tile with a finished edge for completing wall tile layouts.

V-cap tiles — V- or L-shaped tile for finishing the exposed edges of countertops.

Vitreous — Slightly permeable tile. Absorbs .5 to 3% of its total weight in water.

Wall tile — Tile intended for use on walls. It is generally thinner than floor tile and should not be used on floors or countertops.

Water absorption or permeability — The measure of the amount of water that will penetrate a tile when it is wet. Measurement ranges from non-vitreous to semi-vitreous to vitreous to impervious.

Waterproofing membrane — A flexible, water-proof material installed in sheets or brushed on to protect the subfloor from water damage.