What to Know About Bathroom Wall Waterproofing?

Written By Adam Paul - Waterproofing Expert

Bathroom wall waterproofing is installing a water-impervious layer on the bathroom walls where the water is splashed. You can use both liquid and sheet waterproofing membranes for this. The waterproofing height of the wall is varied with the fixtures placed in the bathroom space. The most problematic bathroom wall damages are mold and mildew growth, paint or wallcovering damage, structural damage, wall tile and grout damage, and odor issues.

You should waterproof the bathroom wall materials such as tiles, wood, stone, bricks, burnt clay, cork, vinyl and epoxy. The maximum height of the bathroom wall waterproofing is 6 feet (183 cm), which is the shower wall. You can waterproof existing bathroom walls by using a waterproof sealant, paint or epoxy grouts. It will prevent many water-related issues in the bathroom.

Waterproofed bathroom walls can be damaged due to improper installation of the waterproofing membrane, physical damage, chemical damage, temperature fluctuations, and higher water pressure. You can protect the bathroom wall waterproofing by installing proper waterproofing, avoiding physical damage, using mild cleaning agents, controlling temperature, and doing regular maintenance. You can use a bathroom without waterproofing the walls by following these methods: using shower stalls, shower curtains or doors, bath mats, avoiding overflowing, and doing quick cleanups.

What is Bathroom Wall Waterproofing?

Bathroom wall waterproofing is applying water impervious layer on the bathroom walls up to these heights: 6 feet (183 cm) height splash zones in the shower wall,3 feet (92 cm) height at the toilet wall, 2.5 feet (76 cm) height at the bathtub floor, and 4 feet (122 cm) height at the sink wall.

Bathroom waterproofing is a combined process of waterproofing the bathroom floor and the bathroom walls.

What are 5 Bathroom Wall Water Damages?

If you do not waterproof your bathroom walls properly, you can see the below 5 common problems.

1. Mold and Mildew growth on the walls: Mold and mildew can grow on the bathroom walls, corners, and other surfaces if you do not waterproof the bathroom walls.
2. Paint and wallcovering damage: Unprotected walls can absorb moisture. This will cause to to peeling paint, bubbling wallpaper, or discolorations.
3. Structural damage: Water can seep into bathroom walls due to leaking. This can weaken materials, rot and reduce the structural stability.
4. Wall tile and grout damage: Bathroom wall tiles and grouts can be damaged due to heavy water leaking from the bathroom. This causes biological flux in the space and reduces the strength between the materials.
5. Odor issue: Mold and mildew can grow due to the bathroom wtaer leaking. When the grown mold and mildew stagnate with bathroom water, odor can be produced in the bathroom.

What Wall Materials Should I Waterproof in the Bathroom?

You should waterproof these 10 bathroom wall materials. Because these materials are not water-impervious, their seams and joints can leak water.

1. Ceramic tile
2. Porcelain tile
3. Wood
4. Natural Stone
5. Bricks
6. Burnt clay tiles
7. Concrete
8. Cork
9. Vinyl
10. Epoxy

What Waterproofing Membranes Can Be Used for Bathroom Walls?

You can use below 8 waterproofing membranes for the bathroom wall water stops. All of these waterproofing membranes can be categorized into liquid and sheet membranes. Liquid waterproofing membranes are suitable for uneven surfaces, floors, and walls, while sheet waterproofing membranes are suitable for bathroom floor waterproofing.

1. Cementitious waterproofing: Cementitious waterproofing can be applied as a liquid coating on the bathroom floor and walls to stop water leaking.
2. Epoxy waterproofing: Epoxy waterproofing is an impermiable, liquid waterproofing membrane that can be used on the bathroom floor and walls. Epoxy can be used for old bathroom water stops also.
3. Acrylic coating waterproofing: Acrylic waterproofing is a liquid waterproofing membrane that can be used for bathroom floors and walls.
4. Bituminous coating waterproofing: Bituminous coating waterproofing is a liquid waterproofing membrane that can be used for both bathroom walls and floors to prevent water leaking.
5. EPDM Rubber waterproofing: EPDM rubber waterproofing is a sheet waterproofing membrane that can be used to waterproof bathroom shower areas, walls and floors.
6. HDPE waterproofing: HDPE is a sheet membrane waterproofing that can be used to waterproof the bathroom wall and floor.
7. PVC waterproofing: PVC is a sheet membrane waterproofing. PVC can be used to waterproof the shower area and bathroom waterproofing.
8. Polymer waterproofing: Rubber polymer can be used as positive side waterproofing for the shower areas.

How High of a Wall Should I Waterproof in the Bathroom?

You should waterproof the bathroom wall height as below

1. Shower wall splash zone height: 6 feet (183 cm)
2. Toilet wall height: 3 feet (92 cm)
3. Bathtub wall height: 2.5 feet (76 cm)
4. Sink wall height: 4 feet (122 cm)

Can I Waterproof the Existing Bathroom Wall?

Yes, you can waterproof the existing bathroom walls by using waterproofing sealers and paints, epoxy grouting, and silicone caulk. Before applying any waterproofing agent on the bathroom's existing walls, you should thoroughly clean them to remove mold and mildew and repair any cracks or damage to the walls.

After applying the waterproofing on the walls, you should improve the proper ventilation and prevent excessive humidity in the bathroom to prevent moisture-related issues to the walls.

Read More: How to Waterproof a Bathroom Wall?

Is the Shower Attached Wall Need Waterproofing?

The shower attached wall should be waterproof up to 6 feet (183 cm) because an open shower can spread the water to the wall heavily. Therefore, the mounted wall is the heavy water-damaged wall in the bathroom.

How to Damage a Bathroom Wall Waterproofing?

Bathroom wall waterproofing can be damaged due to these 5 common reasons. A damaged waterproofing coating of the bathroom wall can penetrate the water inside the structure and it cause to water related issues to the structure.

1. Improper installation: If the bathroom wall waterproofing is not installed properly, it can be damaged easily. Improper bathroom wall waterproofing is using the wrong waterproofing membrane, laying with a thinner thickness, applying fewer coatings, not following the manufacturer's guidelines, and using non-skilled labor.
2. Physical damage: Bathroom wall waterproofing sealant can be damaged when the wall is hit by something, as it can damage to inside the substrate.
3. Chemical damages: The bathroom wall waterproofing layer can be damaged due to using harsh chemicals while cleaning.
4. Temperature fluctuation: Due to temperature fluctuations, the structure can be expansion and contraction. As a result, the waterproofing layer on the bathroom wall can be damaged easily.
5. Water pressure: High water pressure leakage can cause to damage the waterproofing layer.

How to Protect Bathroom Wall Waterproofing?

A bathroom wall can be protected by following the below 6 steps.

1. Proper waterproof installation: You should use the recommended waterproofing membrane and product with skilled labour for the proper waterproofing installations for the durable waterproofing coating on the bathroom walls.
2. Avoid physical damages: Do not let to drill, cut, and nail to the bathroom walls because this can damage the waterproofing membrane.
3. Use mild cleaning agents: You should use mild cleaning agents instead of harsh chemicals to clean the bathroom floor cleaning.
4. Control the temperature: Do not let too much dry and wet the bathroom floor, which causes temperature fluctuations.
5. Do regular maintenance: You should check for regular maintenance and repairs for the bathroom maintenance. You should observe cracks, tears, and loose materials in the joints and do immediate repairs.
6. Use a sealant: You can use a sealant above the bathroom wall materials. This will prevent the water from penetrating the walls. 

How to Use a Bathroom Without Waterproofing Walls?

You can use a bathroom without waterproofing the walls using the following methods:

1. Use shower stalls: Shower stalls do not allow water to spread on the bathroom walls. Hence, when you use a bathroom stall, you should not do bathroom waterproofing.
2. Use shower curtains or doors: Shower curtain or doors allows the accumulation of water in the bathtub areas without spreading over the walls. This will prevent the water from leaking through the walls.
3. Using a bathmat: Place a bathmat near the bathtub area. This will prevent water from being tracked across the bathroom floor and reduce the chance of water reaching the walls.
4. Avoid overflowing the bathtub: Do not allow to overflow the bathtub area, as walls can seep the water.
5. Do quick cleanup: You can wipe down the wet surfaces when the water splashes on the wall.