Planning a small bathroom

Small bathrooms are won or lost on a few centimetres. The fittings themselves are rarely the problem: what goes wrong is the space around them, the direction a door opens, and where the drain already is.

Start with the soil pipe, not the suite

A basin or a shower can be moved almost anywhere, because the waste pipes are small and can run at a slope inside a floor or a boxed duct. A toilet is different. Its waste is wide and needs a consistent fall to the soil stack, so moving it even a metre can mean lifting a floor or building a step.

Find where the soil stack is before drawing anything. A layout that keeps the toilet near it is usually far cheaper and less disruptive than one that looks tidier on paper.

Leave the clearances

Fittings need space in front of them to be usable. As rough working figures, allow around 700mm of clear floor in front of a basin, 600mm in front of a toilet with a little width either side of the pan, and 700mm beside a bath to stand and dry.

These overlap happily. The space in front of the basin can be the same space used beside the bath. What cannot overlap is anything fixed, so measure the clear floor once with every fitting drawn in.

The door is usually the problem

An inward-opening door sterilises a large arc of the only floor you have, and in a small room that arc is often the difference between workable and not.

Rehanging it to open outward is a cheap change with a large effect, provided the landing or hallway outside can spare the space and the door does not swing into a stair. A sliding or pocket door removes the swing entirely, at more cost and with a wall that must be thick enough to take it.

Shower rather than bath, carefully

Replacing a bath with a shower enclosure frees real floor area and suits most households. Think about it twice if small children live there, or if the house is the only bathroom in a property that may be sold to a family, as a house with no bath is harder to sell than people expect.

A shower over a bath is the compromise, and it works as long as the screen is fixed properly and the sealing is done well.

Plan the ventilation at the same time

Ventilation is easier to install while walls and ceilings are open than to retrofit afterwards. Decide where the fan goes and how its duct reaches outside while the room is stripped, not once it is tiled.