Upstairs changed the location of the toilet.

This question should be said to have nothing to do with the fourth floor. The reason for this is the following：

1. Is there a corner vent in your bathroom? If so, it has nothing to do with the fourth floor.

2. Is there an "S-bend" in the original drainage system of your bathroom, such as floor drain, toilet drain hole and mop pool drain hole? This "S-bend" is very important. It is an important organ that "blocks" odor.

Therefore, the smell of your house should have nothing to do with the fourth floor.

So, what is the reason for the obvious odor in your home? The possibilities are as follows:

1. If there is a "vent" in the corner of the house, please check whether the vent is clear, especially whether the "mouth" on the top floor is blocked. If there is, make it comfortable and clean it up.

2. Does every sewer pipe in the house have an "S-bend"? If not, you'd better install it, which is the most effective. If it cannot be installed temporarily, it can be handled as follows:

A, the "water deflector" at the lower part of the washbasin has an "S-shaped bend", or the drain pipe under the water deflector has an "S-shaped bend", which is also good.

B, the mop pool can be slightly raised and treated as "A". If you can't handle it this way, use a plastic seal with a seal. It is good to block the sewer at ordinary times.

C, the floor drain part is difficult to deal with. Now that it has been completed, no major changes will be made. Just replace it with a floor drain that smells like gambling. You can't seal it.

I try my best to help you.