What is a toilet pit distance (pit spacing)?
Toilet pit distance (pit spacing) is the distance between the center of the toilet drain outlet and:
a.) the backside of the toilet (ground drainage toilet with S-trap – toilet with bottom discharge);
b.) the bottom of the toilet (back drainage toilet with P-trap – toilet with rear discharge).
There are three sizes of pit distances for the ground drainage (bottom discharge) toilet: 250mm (9.84 inch), 300mm (11.81 inch) or 400mm (15.75 inch). So, this is the distance between the backside of the toilet and the toilet drain outlet. The standard (and the most commonly used) pit distance is 300 mm / 11.81 inch for the ground drainage toilet.
For the back drainage (rear discharge) toilet (drainage to the wall, not to the ground), the pit distance is 180mm (7.09 inch). This is the distance between the bottom of the toilet and the toilet drain outlet.
Most of the ground drainage toilets we sell have pit distances 300mm (11.81 inch) or 400mm (15.75 inch), and some selected toilets have a pit distance of 250mm (9.84 inch). Back/wall drainage toilets have a pit distance of 180mm (7.09 inch).
Ground drainage toilet, S-trap
If the bathroom ground drainage pit distance is 260mm (distance from the tiled wall to the center of the sewer pipe on the ground), 250 mm pit distance toilet can be installed, however 300 mm and 400 mm pit distance toilets cannot be installed. If the bathroom ground drainage pit distance is 420 mm, all toilets with the ground drainage can be installed, but the best is 400 mm pit distance toilet as it goes closer to the wall.
Wall drainage toilet, P-trap
If the bathroom has a wall drainage (not the ground drainage), toilet with back drainage (180mm pit distance) should be chosen.
If you are unsure what toilet pit distance you need, send us a simple drawing / photo of your bathroom with the dimensions and we can help to confirm it for You.
Toilet pit distances explained in the images: