Damp exterior walls: causes and how to treat them

Your exterior walls serve as protection against all types of weather conditions. They’re exposed to harsh weather and wind. Usually, that’s not a problem, but over time, and especially in older homes, moisture can become an issue. When bricks become more porous or joints start to crumble, water can begin to seep in. The result? A damp exterior wall that not only loses its protective power but also allows moisture to move inward. Spotting and treating the problem early is key to avoiding more serious damp issues.

How to recognise a damp exterior wall

It’s perfectly normal for your exterior walls to be wet after rainfall; that’s not an issue in itself. It only becomes a problem when the walls take a long time to dry afterwards. That’s a sign that moisture is penetrating deeper into the surface. If you observe cracks or joints start to crumble, these are clear red flags. Flaking façade cladding, such as render, that starts turning black or discoloured, is also a common sign of moisture trouble due to a damp exterior wall.

Danger of indoor moisture problems

Once the damp from the exterior starts making its way into the building, the problems worsen. You’ll then have to deal with peeling paint or wallpaper, wood rot, cold and clammy walls, musty odours or damp patches. Timely action is highly recommended! Fortunately, you can easily tackle this problem yourself.

How to tackle a damp exterior wall in 3 steps

Several reliable products can help solve the issue. Here’s a step-by-step guide to help you permanently deal with a damp exterior wall.

Step 1: Repair damaged joints

The first step is always to fix any loose or crumbling joints. This is easy with Wall Protect Quick Joint, a ready-to-use grout. Start by removing any loose material, then apply the product using a standard sealant gun, the same type you would use for silicone. This allows you to tackle all joints between the brickwork or fill cracks in concrete. Once dry, Wall Protect Quick Joint can be painted over if necessary.

Step 2: Treat the lower part of the wall

Treat the base of your wall with Rain Protect Extreme. This ready-to-use wall coating makes your wall waterproof in a single coat and prevents moisture from penetrating into the surface. What’s more, Rain Protect Extreme repairs and reinforces your façade. Another handy advantage is that it’s washable and paintable. It also repels dirt and offers long-lasting protection. This ensures that your efforts remain visible for a long time.

Step 3: Treat the entire façade

If you want to treat a wet exterior wall, you can choose a transparent or ‘white’ coating to solve the problem.

With the transparent Rain Protect Liquid, you apply an invisible, breathable coating to your exterior wall. It protects the surface against driving rain and dirt without changing the appearance of your home.

Rain Protect White is a moisture-repellent, white coating with extreme covering power and elasticity. It creates a moisture-resistant barrier on the wall. Thanks to its elasticity, it’s also suitable for very rough walls. Rain Protect White also offers excellent UV protection.

All these products are quick and easy to apply and give you perfect results in no time. They don’t just solve your moisture issues; they help keep your façade looking beautiful for years to come.