Understanding the Difference Between 300mm and 400mm Toilet Rough-In Measurement

The toilet rough-in distance comes in different types, and it is essential to pay attention to this before purchasing to avoid affecting the proper use of the toilet. Let's take a look at the differences between toilets with a rough-in distance of 300mm and 400mm.

What are the differences between toilets with a rough-in distance of 300mm and 400mm：

The rough-in distance refers to the distance from the center of the toilet's drain pipe to the wall. There are two common types: 300mm and 400mm. A toilet with a rough-in distance of 300mm means that the distance from the center of the toilet to the wall is 300mm, while a rough-in distance of 400mm means that this distance is 400mm.

It is crucial not to have the toilet too far from the wall, as it may affect the overall aesthetics of the bathroom. For example, if the rough-in distance is 400mm and you install a 300mm rough-in toilet, there will be a 100mm gap. Conversely, if the rough-in is 300mm and you choose a 400mm toilet, installation will not be possible.

How to choose a toilet for the bathroom：

1、Choose a suitable type of toilet based on the actual situation in the bathroom. First, determine the drainage method—whether it is wall-mounted or floor-mounted—and then select the installation position and reserve the toilet outlet according to the rough-in distance to ensure proper installation.

2、When purchasing a toilet, check its quality. You can test the weight of the toilet; a heavier toilet usually indicates better quality, while a lighter one may suggest issues. Additionally, inspect the glaze surface for smoothness and uniformity.

3、You can also conduct a test by adding some blue dye into the toilet tank to check for leaks. If blue water seeps out, it indicates a leak in the toilet. Moreover, assess the flushing performance and whether it produces excessive noise.

In summary：we have introduced the differences between toilets with 300mm and 400mm rough-in distances and how to choose a toilet for the bathroom. It's crucial to determine the rough-in distance accurately and avoid selecting the wrong dimensions, as this can significantly affect usability later on.