Is it necessary to do secondary drainage for sunken toilets?

The first conclusion is that the sunken toilet needs secondary drainage, which is very necessary. Why? Let's talk about "sunken toilets" first.

What is a sunken toilet? The main difference between traditional bathroom and sunken bathroom lies in the architectural structure difference of bathroom. The traditional bathroom is "interlayer drainage". The sewer pipe in the upstairs bathroom is at the top of your bathroom, and the sewer pipe in your bathroom is at the top of your neighbor's bathroom downstairs.

Sinking bathroom is "drainage on the same floor", and the sewer pipe of your own bathroom is at the bottom of your own bathroom, which will be deeper than other rooms. Many new houses are designed like this now.

Advantages and disadvantages of sunken toilet

The advantage of the sunken bathroom is that it is beautiful and quiet. The pipes upstairs will not be exposed to your home, and the noise of flushing will not affect your home. Also, the problem of water leakage in your house will not affect the neighbors downstairs, so solve it yourself. There is also the convenience for the layout and planning of toilets, and the positions of drains such as toilets, sinks and floor drains can be changed.

Of course, sunken toilets also have shortcomings, water leakage is not easy to find, and once it leaks, it will be more troublesome to maintain.

Sinking toilet drainage system

As we all know, the bathroom needs to be waterproof and there will be a floor drain. Usually, water flows away from floor drains and pipes.

However, because the sunken toilet has caissons (which are later raised or filled), and these pipes are just in the caissons, once the pipes leak, the water cannot be drained away and can only be accumulated in the caissons.

The water in the caisson won't drain out. Over time, the accumulated water will penetrate the cement mortar, destroy the waterproof layer, leak downstairs, even cross the bathroom threshold and penetrate into the walls of each room.

So in order to avoid this situation, the sunken toilet needs to be drained twice. Secondary drainage is equivalent to adding an invisible floor drain to the caisson of the bathroom, which can avoid the above-mentioned water leakage problem in the bathroom.

Regarding whether the sunken toilet needs secondary drainage, the first station of reconstruction has been analyzed in detail. If you have any better ideas or different opinions, please leave a comment ~