Toilet set-out guide

Toilet set-out is the distance from the finished wall behind the toilet to the centre of the floor waste (S-trap) or the height of the wall waste (P-trap). Many S-trap pans adjust across a range such as about 140–240 mm, so measure yours before you choose.

How to measure an S-trap

Measure from the tiled wall behind the toilet to the centre of the waste pipe in the floor. Old toilets are often around 100–160 mm; check the product's set-out range covers your number.

P-trap

A P-trap goes into the wall. Measure from the floor to the centre of the wall waste.

Back-to-wall and in-wall

Back-to-wall pans need the waste in the right spot because the pan covers it. In-wall systems need a stud wall to hold the cistern frame.