Bathroom glossary

The technical terms you meet when choosing a toilet, a basin, an LED mirror, a shower or a bathtub, explained simply.

Anti-fog (demister)

A heating element behind a mirror that keeps the glass clear of condensation after a hot shower.

Back-to-wall bathtub

A bathtub with the look of a freestanding model and one flat side that sits against the wall. It uses a standard wall-mounted tap.

Click-clack waste

A basin waste with a plug that opens and closes by pressing on it. Versions designed for basins without overflow are used on countertop basins.

Colour rendering index (CRI)

A score up to 100 that measures how faithfully a light source shows colours. Above 85, skin tones and make-up colours look natural.

Colour temperature

The colour of white light, measured in kelvin (K). Around 3000 K gives a warm white, 4500 K a neutral white and 6500 K a cool white.

Concealed frame

A steel frame with a built-in cistern, hidden in a stud wall or a false wall. It carries the weight of a wall-hung toilet, sets its height and holds the flush mechanism operated by the flush plate.

Copper-free mirror

A mirror whose reflective silver layer is protected without copper. In a humid room, it resists the black spots and darkened edges that appear on ordinary mirrors.

Countertop basin

A washbasin placed on top of a worktop, a vanity unit or a shelf, so that its whole shape stays visible. Its height adds to the height of the worktop.

Fixing centres

The distance between the two threaded rods that hold a wall-hung toilet on its frame. The standard value is 18 cm; the bowl and the frame must use the same value.

Freestanding bathtub

A bathtub that stands on its own, visible from every side, away from the walls. It needs free space around it.

Horizontal outlet

A toilet outlet that leaves the bowl towards the back wall. It is the standard configuration for wall-hung toilets, connected to the drain through the concealed frame.

IP44

An ingress protection rating: protected against solid objects larger than 1 mm and against splashing water from any direction.

Level-access floor

A shower floor at the same level as the rest of the bathroom, without a step, sloping towards a drain. It must be waterproofed before tiling.

Out-of-plumb adjustment

The margin of a wall profile that compensates for walls that are not perfectly vertical. Corsa and Aire Walk-In allow ±20 mm on each side.

Overflow

An opening near the top of a basin or bathtub that drains away excess water before it spills over. Many countertop basins have none and use a non-closing or click-clack waste.

Quick-release seat

A toilet seat that lifts off its hinges without tools, to clean the hinge area properly, and clicks back into place.

Rimless toilet

A toilet bowl without the inner rim under which water usually flows. The open, smooth surface leaves fewer places for dirt and limescale to settle, and is quicker to clean.

Sanitary acrylic

A plastic material used for bathtubs and shower trays: warm to the touch, light and easy to clean. Light surface scratches can usually be polished out.

SMD LED

A surface-mounted LED soldered directly onto a flexible strip. SMD 2835 refers to a chip of 2.8 × 3.5 mm, widely used for even, efficient backlighting.

Soft-close seat

A toilet seat whose hinges slow the lid down so it closes gently and silently, without slamming.

Stabiliser bar

A metal bar linking the top of a fixed glass panel to the wall, which keeps the panel rigid.

Tap hole

A pre-drilled hole in a basin that takes a single-hole mixer. A basin without a tap hole is used with a wall-mounted tap or a tall mixer on the worktop.

Tempered glass

A safety glass heat-treated to be several times stronger than ordinary glass. If it breaks, it shatters into small blunt pieces.

Walk-in shower

A shower without a door, protected by a fixed glass panel, with an open entrance. It is often built on a level-access tiled floor.