How to Repair Water Seepage on Bathroom Walls

The bathroom and kitchen use the most water, especially the bathroom. It has a high usage frequency. During decoration, the workers should apply waterproofing treatment in both areas. Water seepage on bathroom walls is a common problem. It causes issues like dampness, mold, efflorescence, and peeling. If it is behind a bedroom wardrobe, it may corrode the cabinet over time. So, we cannot ignore the problem of water seepage.

In this issue, we will review the causes and solutions of water seepage on bathroom walls. Those in need can save it for reference.

8 Reasons for Wall Seepage

1. Pipe Leakage

If the connection of water pipes is not tight, it will cause leakage and seepage. Also, if the water pipes are of poor quality, they may burst after some time. This will cause wall seepage.

Solution: First, conduct a pressure test to rule out whether the water pipe is the problem. If it is, locate the pipe slot per the layout diagram. Then, chisel the wall to find the water pipe leak. Finally, reconnect or replace it with a higher-quality pipe. This will solve the problem of wall seepage caused by water pipe leakage.

2. Improper tile installation

There are two methods of tile installation: dry-laying and wet-laying. If the bathroom wall tiles are dry-laid, poor work may cause water to collect beneath them. This can lead to dampness and leaks as the water seeps out along the wall.

We recommend changing from dry laying to wet laying. In dry laying, workers spread a 1:3 dry cement slurry evenly. Then, someone places the tiles on top and compacts them with a rubber mallet. Over time, they may fall off the wall. In contrast, wet laying involves applying the cement slurry to the back of the tiles for laying. The process is simpler. The mortar layer is thinner. The tiles are more firmly attached to the wall. This makes them less prone to moisture and water seepage.

3. Improper application of waterproof paint

If someone paints the bathroom walls with waterproof paint, moisture may seep in. This could be due to the improper application of the paint.

Treatment method: Scrape off the original wall paint. Level the wall. Then, apply a new layer of waterproof paint. Note: Just like ordinary wall paint, use a primer first. Then, apply 2-3 coats of waterproof paint. You should space each coat of waterproof paint at least 6 hours apart. This ensures that the paint is completely dry before applying the next coat. Otherwise, the moisture in the wall will be hard to evaporate. The waterproofing will not be good.

4. They did not apply any insulation layers.

In northern regions, winter creates a large temperature gap across the wall. This leads to condensation on the bathroom’s inner wall. This keeps the wall damp for a long time. Eventually, water seeps in, causing efflorescence and mold on the surrounding walls.

Solution: In this case, add an insulation layer. It will keep heat and reduce the temperature difference across the wall.

5. Poor waterproofing

If there are no other issues, it is likely the waterproofing is not done properly. The bathroom walls have severe water seepage after a shower. It improves at other times. Either the waterproofing layer is too thin, or it’s too low.

Solution: Remove the tiles. Redo the waterproofing layer. Then, apply the waterproof coating 2-3 times, with at least 6 hours between each coat. Wait until it is completely dry before applying the next layer, and then re-tile.

6. Wall Cracks

Wall cracks are also one of the causes of bathroom leakage. The solution to this problem is to repair the wall cracks. The specific steps are as follows:

(1) Clear the debris and dirt around the crack to expose the original appearance of the crack.

(2) Use crack repair materials and follow the product instructions for repairs.

(3) Inspect the repaired crack to ensure a good repair effect.

(4) Treat the surface of the repaired wall. It should match the surrounding walls.

Required materials: crack repair materials, surface treatment materials, etc.

7. Water Accumulation in the Ground-Level Sump

Water in the ground-level sump prevents draining the sump beneath the bathroom floor. This causes the walls to become damp and leak. To solve this problem, we should install a drainage pipe at the bottom of the sump. The specific steps are as follows:

(1) Install a drainage pipe at the bottom of the sump. It must not leak and must remain unobstructed.

(2) Install a drain cover at the drainage pipe opening to prevent odors from escaping.

(3) Apply a waterproof coating or a membrane at the junction of the bathroom floor and the sump. This will improve waterproofing.

(4) Fill the sump with lightweight materials. This will reduce its weight and prevent pipe rupture due to settlement.

Required materials: drainage pipe, drain cover, waterproof coating, and lightweight fill.

8. Loose pipe fixtures

Loose pipe fixtures in the bathroom can also cause wall leakage. To solve this problem, we need to reinstall the pipe fixtures. The specific steps are as follows:

(1) Turn off the water supply; remove the relevant pipes and fixtures.

Reinstall the pipes using the right fixtures. They must be secure and leak-free.

(3) Seal the fixtures with materials such as sealant to prevent water leakage.

(4) Conduct a water retention test after reinstallation to check the waterproofing effect.

Required materials: pipe fixtures, sealant, installation tools, etc.