National standards and provisions for subsidence of 2.5 centimeters in kitchen and toilet floors
National standard "Code for Acceptance of Construction Quality of Building Ground Engineering" GB50209-2002
1. Mandatory Provision 3.0.15 The elevation difference between the ground surface of toilets, kitchens and buildings with drainage (or other liquid) requirements and the connecting surface layers should meet the design requirements.
(The design drawing generally stipulates that the height difference between the structural surface of the toilet and bathroom, kitchen, and balcony and the adjacent structural surface is 50MM. In practice, more than 20-30MM is acceptable. The height difference between the squatting toilet and bathroom and the adjacent structural surface is 50MM. The height difference design of the structural surface is generally 250MM)
2. 4.10.5 After the waterproof material is laid, it must be inspected by water storage. The water storage depth should be 20~30MM. If there is no leakage within 24 hours, it is qualified and recorded.
3. Mandatory provision 4.10.8 A waterproof isolation layer must be installed on the floors of toilets and bathrooms and buildings with waterproof requirements. The floor structure must use cast-in-place concrete or a whole precast concrete slab, and the concrete strength grade should not be less than C20; except for the door opening, concrete flanging should be made around the floor, and its height should not be less than 120MM. During construction, the structural layer elevation and reserved hole locations should be accurate, and random drilling of holes is strictly prohibited.
(The waterproof isolation layer is waterproof membrane, waterproof coating or waterproof mortar, concrete; the concrete flange, that is, the concrete around the toilet and bath room, should be higher than the adjacent structural surface to prevent leakage.)
TXM should pay attention to water storage inspection! Otherwise it will affect the relationship between the neighbors upstairs and downstairs! Affects the civilized construction of the community!