What should I do if there is water in the caisson of the bathroom?

Water seepage in toilet is a common problem in construction. Among them, the toilet with squatting caisson structure is particularly troublesome. On the one hand, it is difficult to repair the seepage, and on the other hand, there are many reasons for the seepage, which are not easy to find. If the caisson water can be avoided, the probability of water leakage in the bathroom will be greatly reduced. Through the reverse repair of the project, I observed the causes of water accumulation, some of which were caused by a single reason; Some of the above two reasons are as follows.

1) The shape of the sewage outlet of the toilet is irregular, and there is a big gap after the sewage outlet is inserted into the water inlet of the PVC pipe. Some of them have no waterproof glass glue, and some have waterproof glass glue, but because of the big gap, the glass glue was washed away by water. The water for flushing the toilet enters the caisson through the gap in the joint.

2) Although the structural plate and wall at the bottom of caisson are waterproof, the surface structural plate is not waterproof. Water oozes from the floor when the toilet is cleaned. Once the waterproof layer of the bottom plate fails, the toilet will leak.

3) The open caisson panel is equipped with a drainage floor drain, but the open caisson floor is not equipped with a secondary drainage floor drain, or although it is equipped with a secondary drainage floor drain, it is blocked by mortar during the panel construction, and the open caisson becomes a dead puddle. Long-term accumulated water cannot be discharged.

4) The secondary drainage floor drain of caisson bottom plate is not installed at the lowest place, but the caisson bottom plate has no slope, so the floor drain is useless. Undeniably, the construction of the waterproof layer in the bathroom is very important, but if the water accumulates for a long time, once the waterproof layer fails, the bathroom will leak. If we can actively control water and prevent caisson from accumulating water, it will be of great help to overcome leakage.

In view of the above analysis, the following points should be achieved in the construction:

1) When selecting a toilet, check whether the sewage outlet is a standard circle. Glass glue should be applied in time after installation.

2) The panel of caisson should also be waterproof.

3) The floor drain shall be installed on the surface and bottom structural plate of caisson, and the floor drain shall not be blocked.

4) The caisson floor should have a slope, and the secondary drainage floor drain should be located at the lowest place.

1. Waterproof structure diagram of caisson bathroom

(1) What is a caisson bathroom? What is its structure?

Red is the waterproof layer. General developers have done waterproof. We must do a water storage test first. If there is water seepage, the bottom waterproof layer must be redone. Value until it does not penetrate. After it won't penetrate, make water supply pipes and sewage pipes. The sewage pipe must have a slope, and a sewer pipe is made at the lowest part of the sewage pipe, which is what everyone calls secondary drainage. If the waterproof layer above leaks to the bottom over the years, the water in the caisson can also be drained. ) This will play the role of secondary insurance.

After the water supply pipe and sewage pipe are completed, cover the sewage pipe with water and sediment, and waterproof it again by using the slope from the sewage pipe to the secondary drainage pipe. Its main purpose is to prevent the water in the caisson from flowing under the sewage pipe to produce water. Then use red bricks or cement slabs as support columns, and put the prepared cement slabs (6-8 cm cement slabs made of steel bars, pebbles and cement) on the support columns. Leave him empty inside. Then do cement mortar leveling. The leveled cement mortar is waterproof again. Do water storage test after waterproofing is completed. If it won't penetrate, put some clean cement or dry cement mortar to protect the waterproof layer and you can lay the floor tiles.

(2) How to judge whether your home is a sink toilet?

Simple and practical judgment skills: if you don't live on the top floor, look up at the roof of your bathroom. If there is only one main drainage pipe leading out from its own corner, and there are no other floor drain pipes or traps, P bends and S bends, this is generally what we call caisson toilets.

Another way to judge whether it is a caisson bathroom: look at the floor of your bathroom, there are generally dozens of centimeters of pits, in which you can see the layout of the drainage pipes in your bathroom. The floor of the bathroom is about 30 cm below the room, and there is no horizontal drainage pipe on the ceiling of the bathroom.

(3) Advantages and disadvantages of caisson toilet.

Advantages: Because the maintenance and repair of caisson bathroom pipes are all carried out on the same floor of sanitary ware, it does not interfere with the lower-level residents, and solves their own problems without bothering downstairs. However, the traditional bathroom pipes are arranged in disorder, and they interfere with each other during maintenance and use, which brings inconvenience to people's lives. Another advantage of the design is that toilets and bathtubs can be placed at will. Unlike ordinary toilets, toilets are fixed in position and cannot be moved.

Disadvantages: First of all, if there are three major problems, such as broken water pipes, weak joints, water leakage, drainage pipes blocking the ground, and manual dredging, it is necessary to pry open the floor to solve them. Secondly, we should be waterproof, otherwise sinking will become a sewage pool.

2. Three methods of caisson treatment and their evaluation.

At present, there are three ways to treat caissons in toilets:

1) waste residue backfilling has the advantages of simple construction and low price (generally around 300 yuan), but the disadvantage is that a certain part of the floor slab is not allowed to be overweight, which will be phased out in the future.

2) Cement precast slab: firstly, prepare the cement precast slab (which needs reinforcement) outside, and then cover it on the caisson. This method is slightly more expensive than the waste residue backfilling method (generally around 400 yuan), and it is a trend of caisson treatment in the future. At present, some cities have requested caisson treatment in this way; After overhead, secondary waterproof treatment (caisson treatment) is adopted. The cost is high, because the overhead floor must be cast-in-place concrete slab or precast slab. But the second method is to waterproof the old structure before overhead. In fact, it is also cushion treatment, and then leveling with 20~45mm mortar, looking for slope layer-waterproof layer-waterproof protective layer of cement mortar-brick surface layer. (Plus the old structure is waterproof once, which is a double waterproof treatment.

3) ceramsite backfill, which is the best way, but the price is also the most expensive (above 800 yuan). Buried with moisture-absorbing and moisture-proof ceramsite, filled with broken brick fine sand. (Fill the sedimentation tank). Actually, it's pad therapy. After the fine sand with broken bricks is filled, a layer of concrete with a thickness of 50~ 100mm should be made -20 ~ 45 mm mortar leveling-waterproof layer-cement mortar waterproof protective layer-brick surface layer. Moisture-absorbing and moisture-proof ceramsite landfill can be changed into fly ash mixed with broken bricks landfill.

Of these three treatments, the third one is more expensive and effective. The second one is cheaper and the effect is average. The first one is the cheapest, and it is also prone to renovation accidents in the later period.

Strictly speaking, the latter two schemes also have problems. 1) If there is a problem with the filling material, the surface layer is even more problematic. 2) This process (high cost) is not needed. Cement slag filling (well done), 50 (or above) fine stone concrete cushion, and then rigid waterproof layer and elastic waterproof layer (important and necessary).

It should be noted that the plain cement slurry on the surface of the tile should be equipped with a waterproof agent-the purpose is to isolate the ground sewage from the bathroom on the surface of the tile, and then flow into the floor drain to prevent it from entering the mortar on the bonding layer of the tile, so as to ensure that the bathroom will never smell.

3. Schematic diagram of caisson treatment.

4, caisson backfill construction method

1) Before the caisson is backfilled, the caisson foundation shall be waterproof, and a slightly higher waterproof layer shall be provided along the periphery of the caisson. It is suggested that it is best to combine rigidity with flexibility.

2) After the waterproof layer is completed, see if the developer has secondary drainage in the reserved caisson. The main function is to avoid water leakage caused by waterproof backfill at the grass-roots level, and the aging seepage at the pipeline interface can be discharged through the secondary drainage pipe (which plays the role of backup or double insurance).

3) Enter the backfill procedure.

4) When backfilling to the secondary drainage outlet, the drainage outlet should be in the lowest position after leveling, which is convenient for drainage (water flow principle).

5) Continue the backfill procedure.

6) After backfilling, the mortar shall be leveled.

7) Waterproof base course again. This waterproof layer is very important. It is recommended to find a professional construction team)

8) Closed water test after waterproofing. It's best to turn off the water for a few more days to see if there is any leakage in the wood, which is convenient for maintenance before sticking bricks.

Note: In fact, lightweight ceramsite is the best backfill material, and the above are the usual caisson treatment procedures for caisson toilets. The cost performance ratio is relatively high, and the price of ceramsite treatment is slightly higher, so the treatment procedure is slightly complicated, because it will involve materials such as square and steel mesh and construction. Another method is that the surface is overhead, and there is no need to backfill at all. Of course, it is relatively more reasonable after processing.

5. Secondary drainage

(1) What is secondary drainage?

Secondary drainage is a drainage method to prevent the water pipe buried in the bathroom from leaking and the floor from seeping to the downstairs of the owner's house. Because the bathroom will leak into the caisson after long-term use, and then accumulate in the caisson, cement will leak to the downstairs more or less after long-term soaking, and secondary drainage just solves this problem. Owners should pay attention to indoor water pipes when decorating, and it is best to seal them with asphalt, so that even if the interface position is not completely sealed during construction or used for a long time, it will not leak.

Case: When the prospective owner of a real estate repossesses the building, it is found that the toilet sewage pipe has reserved the position of secondary drainage, but there is no secondary drainage, and the kitchen has not reserved the underground drainage pipe. Long-term use will cause water leakage downstairs.

Suggestion: It is best for prospective owners to soak the toilet in water for 2 to 3 days when taking over the building to see if there is any water leakage. If there is water leakage, they can find a property management company to coordinate and deal with it, and then check and accept it after maintenance. Caisson should be waterproof first, and then drained for the second time to ensure that it is not afraid of water leakage. Secondary drainage is actually adding a floor drain in the open caisson. If the water pipes in the caisson are not well connected, the water can be discharged through the floor drain to prevent the sewage from accumulating in the caisson and infiltrating into the downstairs residents.

(2) Secondary drainage construction

One of caisson treatment methods: cement precast slab (empty in the middle of caisson), mainly considering the following two points: 1, property permission; 2. The price is relatively cheap. Yesterday, bricklayers came to inspect the site. After he looked at my caisson, he said that secondary drainage was not allowed.