Mastering Toilet Rough-In Distance: A Comprehensive Guide

Everyone knows that before installing a toilet, it is necessary to measure the rough-in distance to avoid the situation where the purchased toilet does not fit during installation. Below, I will introduce what the rough-in distance of a toilet refers to.

一、What does the rough-in distance of a toilet refer to

The rough-in distance refers to the distance from the center of the drainage outlet to the wall, known as the pipe center distance. The specific rough-in distance needs to be determined based on the water outlet type of the toilet. Generally, for a horizontal drainage outlet, the rough-in distance for a direct flush toilet is about 180mm, while for a vertical drainage outlet, a siphonic toilet is used, with common rough-in distances of 380mm, 400mm, and 580mm. When measuring the rough-in distance in an unfinished house, it is necessary to account for the dimensions occupied by the wall tiles after they are installed.

二、What are the specifications for toilet rough-in distances

1、The specifications for toilet rough-in distances are mostly predefined, mainly referring to the distance from the center of the toilet drainage pipe to the edge of the wall. The market mainly offers the following specifications: 300mm, 350mm, 380mm, and 400mm. Among these, 350mm and 400mm are the more commonly used sizes.

2、This measurement needs to be taken accurately in advance. Generally, there are two types of drainage methods: horizontal drainage and vertical drainage. The rough-in distance for a horizontal drainage outlet is usually about 180mm. The situation for vertical drainage is more complex, with several common rough-in distances such as 380mm or 400mm, and additionally, 580mm.

3、If the wall tiles have already been installed, when measuring, if the distance is 400mm, the actual requirement should be considered as 380mm due to the manufacturer's allowance of 20mm, which accounts for the thickness of the tiles.

4、When measuring the rough-in distance in an unfinished house, it's essential to deduct the dimensions occupied by the tiles once they are installed.

In summary：this concludes the introduction to what the rough-in distance of a toilet refers to. It is the distance from the center of the drainage outlet to the wall, known as the pipe center distance. The specific distance must be determined based on the toilet's water outlet type, and it is crucial to understand it before making allowances to avoid the situation where the toilet cannot be installed.