Do Bathroom Walls Need to Be Waterproofed? (Quick Answers)

We can all agree that bathrooms are that one place in our house that is most prone to water and moisture-related damage as it is constantly getting wet. Therefore, we should invest in making the walls and other surfaces in our bathroom protected to avoid constant repairs.

Do bathroom walls need to be waterproofed?

Bathroom walls are constantly getting wet which can cause moisture to leak through them. This combined with low ventilation causes mold. Waterproof walls can prevent this and stop any major structural damage to your bathroom walls. It is best to waterproof the bathroom walls while it is being built.

Do bathroom and shower walls need to be waterproofed?

Waterproofing bathroom and shower walls has a lot of benefits and prevents long-term damage to the walls. In order to protect the walls, it is crucial to waterproof them even if it might end up costing more and will take longer for your bathroom to be ready.

Structural damage:

Bathrooms usually have poor ventilation which already delays the drying process considerably and when the walls are not waterproof moisture seeps inside and causes structural damage.

In most cases they are not visible until it’s too late to fix it and the wall would need to be taken apart completely to repair it. The damage will be worse in humid places due to the moisture present in the environment.


Condensation can occur within the walls leading to paint discoloration, mold growth and also wood decay. Vapor from the bathroom can affect the air quality indoors and cause mold problems in adjacent rooms.

Additionally, when excess moisture begins to accumulate inside walls it can cause heat transfer which may result in heat loss in the bathroom.


Damp places are the breeding grounds for pests and microorganisms such as mold, this can cause various health issues. This needs to be prevented from the start as mold and wood-decay fungi can live for a long time in the walls with no visible signs.

Maintenance and repairing costs:

When the moisture content in walls become too high, it will lead to cracking, blistering, peeling paint, rotten wood and severe mold infections which will require the assistance of a professional to fix.

This maintenance and repair will be costly, much more than getting waterproof walls beforehand.

How do you waterproof bathroom walls?

Even though it is advisable to waterproof your walls while you are building your bathroom and is significantly less bothersome. There are still ways for you to protect your walls from moisture damage after building your bathroom.

Shower plug sealant:

Shower Plug is a waterproofing sealant for tiles, grout and other masonry surfaces. It is a clear, undetectable liquid that can be brushed over the walls and then wiped away which then leaves your walls protected.

Gypsum wall panels:

Gypsum bathroom wall panels can be fixed on your walls to make them waterproof. As they do not deteriorate when exposed to water and moisture and also protect the wall beneath.

Silicone based caulk:

Silicone-based caulk can be used to seal cracks and holes between walls and floors to make them waterproof as this stops moisture from getting inside the walls.


Glossy paints can ward off water splashes and condensations. Satin, eggshell or semi-gloss paints are a good option if you want to waterproof your walls.

All these options work to make your bathroom walls waterproof but it is important to regularly check if they are still holding strong or need a retouch.

Do I need to waterproof shower walls before tiling?

Waterproofing shower walls before tiling is the best option. It can save you a lot of money and time when it comes to maintaining your shower walls. As it helps keep the walls protected and waterproof from within and increases the longevity of your walls.

If you decide to waterproof your walls after tiling it will be effective but need to be redone as it will wear off with time and use.

How do you waterproof a shower wall before tiling?

As waterproofing a shower wall can be beneficial for both short and long-term use, it is best to know the materials that will be required and also the way to do it properly.

Clean the area:

Before you start, make you’re your floors are clean and clear of any dust, dirt or debris. A broom and dustpan can be used to ready the floors.

 Apply primer:

You can now begin to apply the primer by pouring it in a bucket or a roller tray. And start applying it from the back corner and work your way around the walls with the help of a paint roller.

Seal gaps:

After the primer has set, it is now time to seal the gaps in the walls using silicone. You can use a paint scraper to remove any excess silicone and leave it to dry for 24 hours.

Apply waterproofing agent:

You should begin applying the waterproofing agent beginning from the back corner of the bathroom. Use a roller for smooth and precise application.

Apply waterproof membrane:

It is now time to apply the waterproof membrane to the joints.

Begin by cutting the waterproof membrane into lengths of the bathroom walls and lay it down in a way that half is on the wall and the other half is laying on the bathroom floor covering the crack.

Paint over the membrane with a paint roller or brush using the waterproofing agent to stick the membrane down. You need to repeat this over all the gaps.

Rest the area:

To finish off, paint the rest of the floor and let it dry for 24 hours.

Add waterproof layer:

Finally, after everything has dried completely, apply a final layer of waterproofing to the bathroom wall and floors and let it dry for 24 hours.

Can you waterproof a bathroom yourself?

It is possible to waterproof a bathroom by yourself as long as you have some experience and knowledge about what to use and how to use it.

You can easily apply silicone or apply the paint. But it is best to let a professional handle the application of waterproof membrane on the floors, walls and seams as it is pertinent that this job is done correctly and with fine precision.

What areas need to be waterproofed in a bathroom?

Some areas in the bathroom have a higher risk of getting damaged then others like the area surrounding the shower or near the sink.

So, the areas that need to be covered at the very least while you are waterproofing your bathroom should be the entire floor within the shower’s reach, 100mm over the tiled base, 150mm up the wall inside the shower walls, the vertical angle between two walls in the shower by 1800mm high, the entire floor of the shower if the flooring is made of timber, plywood, particleboard or if it is situated above the ground floor of the house.

Is there a waterproof paint for shower walls?

Shower walls can be protected with waterproof paint. Latex enamel, oil based enamel and acrylic paint are good choices for the shower area as they prevent water and moisture from penetrating the wall.

Semi-gloss paints work well but the glossier the pain, the more it will resist water and will be easier to clean.

How do you waterproof a painted shower wall?

If your painted shower wall can’t prevent moisture from seeping inside that means it doesn’t have a strong enough waterproof barrier or has worn down with time.

You can fix this by applying coats of acrylic sealant over your painted walls. It is transparent, therefore won’t change the color of your paint and will also increase the surface durability of your shower walls.

Do peel and stick tiles work in shower?

Peel and stick tiles won’t work out well in your shower. Even though they are water, moisture and humidity resistant which in theory sounds perfect for the shower. But the truth is even waterproof peel and stick tiles made of vinyl won’t be able to protect the shower walls.

It is challenging to stick every single tile in a perfectly tight manner with just the adhesive they come with. Gaps in them can be an easy way for water to penetrate which can then loosen the adhesive behind and make the tiles come loose.

Are tile stickers waterproof?

Tile stickers can be both waterproof and non-waterproof depending on the material they are manufactured from. Waterproof tile sticker is mainly made of vinyl. They come in several finishes such as gloss, semi-gloss and matte.

What should bathroom walls be made of?

Bathroom walls should be made of materials that are waterproof and can act as a strong barrier against water, moisture and even heat. Some options the can work for your bathroom walls are:

  • Single-sheet plastic
  • Tiles which comes in marble, slate, ceramic, porcelain
  • Acrylic
  • Laminate
  • Stone
  • Glass
  • Paint

Waterproofing shower and bathroom walls will increase their longevity and also help maintain their pristine look on the outside.

The smartest option is to waterproof the walls while you are building it but there are still effective ways to waterproof the walls after they are built or even tiled.

Frequently Asked Questions:

Why Do My Bathroom Walls Sweat Yellow or Brown?

Can Vinyl Wallpaper Be Used In a Bathroom?

Can Bathroom Wall Panels And Tiles Be Painted?

Can Bathroom Wall Panels Be Fitted Over Tiles?

Are Bathroom Wall Heaters Safe or Dangerous to Use?