Tiling glossary
The words the tiling path uses, from backgrounds to grout, in plain English.
- Background
- The wall or floor surface tiles are fixed to, such as plaster, plasterboard, render, screed or backer board.
- Substrate
- Another word for the background: the surface the tiles are stuck to.
- Suction
- How quickly a background soaks the water out of the adhesive laid on it.
- Primer
- A coat brushed or rolled onto a background before tiling, to control suction or help the adhesive grip.
- SBR
- A rubbery liquid (styrene-butadiene rubber) mixed into renders and mortars to help them grip and resist water.
- Tanking
- A waterproof layer put on walls and floors behind the tiles in a shower or wet room.
- Wet room
- A shower room with no tray, where the whole floor is waterproofed and falls gently to a drain.
- Backer board
- A board made for tiling onto, such as a cement board or a waterproof foam board.
- Uncoupling membrane
- A thin layer laid between a floor and its tiles so small movements in the floor don't crack the tiles.
- Screed
- A layer of sand and cement, or a calcium sulphate mix, laid over a concrete floor to make it level and smooth.
- Anhydrite (calcium sulphate) screed
- A flowing screed made with a calcium sulphate binder instead of cement, often laid over underfloor heating.
- Laitance
- A weak, dusty skin that forms on the top of a new screed or concrete.
- Movement joint
- A flexible joint in tiling that lets the floor or wall expand and shrink without cracking or lifting the tiles.
- Perimeter joint
- The movement joint left round the edge of a tiled area, where it meets walls, columns, baths and trays.
- Porcelain
- A dense, hard tile fired so it soaks up almost no water.
- Ceramic tile
- A tile made from fired clay with a glazed face, lighter and softer than porcelain.
- Vitrified
- Fired until the body is glassy and absorbs very little water. Porcelain is fully vitrified.
- Natural stone
- Tiles cut from quarried stone such as marble, slate, limestone or granite.
- Mosaic
- Small tiles supplied on a mesh or paper sheet so they can be laid many at a time.
- Large-format tile
- A big tile, where flatness, adhesive cover and handling all get harder.
- Rectified edge
- A tile edge ground after firing so every tile is the same size with a sharp, square edge.
- Lippage
- When the edge of one tile sits higher than the tile next to it.
- Levelling clip
- A clip and wedge (or cap) that hold the edges of neighbouring tiles flush while the adhesive sets.
- Notched trowel
- A trowel with notches along its edge that combs adhesive into even ridges.
- Solid bed
- Fixing with full adhesive contact across the back of the tile, with no gaps.
- Back-buttering
- Spreading a thin layer of adhesive on the back of the tile as well as on the background.
- Coverage
- How much of the back of a tile is in contact with adhesive once it's bedded.
- Open time
- How long spread adhesive stays sticky enough to bed a tile into.
- Adjustment time
- How long after laying a tile you can still slide it into line without weakening the bond.
- C1 and C2 adhesive
- Cement-based tile adhesive classes: C1 is normal, C2 is improved with a stronger bond.
- T: reduced slip
- The T on an adhesive bag means tiles stay put on a wall instead of sliding down while it sets.
- E: extended open time
- The E on an adhesive bag means it stays workable for longer before it skins over.
- Deformable adhesive (S1 and S2)
- Adhesive that can flex a little: S1 is deformable and S2 highly deformable.
- Dispersion adhesive
- Ready-mixed tile adhesive in a tub, class D, which sets as its water dries out.
- Epoxy grout
- A two-part resin grout (class RG) that is hard-wearing and resists stains and chemicals.
- CG2 grout
- An improved cement-based grout, under BS EN 13888. Extra letters show more qualities.
- Efflorescence
- A white, powdery deposit on grout or tiles, left by salts that water carries to the surface.
- Tenting
- When floor tiles push each other up into a ridge.
- Hollow tile
- A tile that sounds hollow when tapped because there are gaps in the adhesive behind it.
- Gauge rod
- A straight batten marked in tile widths plus joints, used to plan where tiles will fall.
- Datum line
- A level line marked on the wall that the tiling is set out from.
- Setting out
- Planning where every tile will go before fixing, so the cuts are even and the lines are straight.
- Herringbone
- A zig-zag pattern of rectangular tiles laid at right angles to each other.
- Brick bond
- Tiles laid in rows with each row shifted along, like bricks in a wall.
- Trim
- A metal or plastic edge strip that finishes and protects the edge of tiling.
- Silicone sealant
- A flexible sealant used in corners and where tiles meet baths, trays and worktops.