Is there a trap at the toilet drain and the main sewage pipe in the bathroom of the residential buil

Generally, it is a 100mm sewage pipe.

Who is responsible for the leakage of the main pipe in the bathroom, first of all, confirm what is the cause of the leakage of the main pipe. If it is because of the water leakage caused by the decoration, it is the responsibility of the decoration company, if it is not caused by the decoration company, it is the responsibility of the property.

You should be asking about the hole spacing (gross distance), right? There is no fixed standard in our country at present, and it is mainly influenced by other countries. The United States is 305, because the American standard entered China earlier, so China has the most this standard; The Soviet Union was 401 (for the reason of inch conversion), and many engineers in China learned from the Soviet Union in the early years, so the old engineers (design institutes) also followed this standard; The European standard is generally 200-230, but in the past 30 years, Europe has generally used wall drainage, so this standard is rare in China; The wall row is divided into two kinds, one is the ordinary toilet wall row, the required size is to complete the ground to the center of the sewage pipe 180, and the other is the wall-mounted type (now the mainstream way in Europe) Its size is 230

Hello! The exhaust fan can be installed on the top window.

The flue is now generally double-channel, with partitions between the channels to prevent smoke strings, while the exhaust duct of the bathroom generally has only one channel, and some also do two channels.