Why Are The Walls Of My Garage Wet?

So you’ve noticed water on your garage walls that doesn’t seem to be drying up. The very first thing you need to do is to identify the source of the water to find out where exactly the moisture (or leak) is coming from. 

Why Is There Water On My Garage Walls?

There are a fair few reasons why you might be finding water running down or pooling in your garage walls, including the most common:

A Leaking Roof
If there are any flaws in your roofing material or any damage to your garage roof, this could act as the perfect site of entry for water after a heavy shower or snowfall.

Compromised Seals
Whether it’s around windows, doors, utility seams, or between the wall and floor, if a seal is damaged or has come away, it’ll no longer be able to prevent water from flowing in. 

Cracks and Crevices
This could be due to damaged concrete, broken windows, a faulty garage door, a damaged roof, warped wood… there’s a whole host of reasons why cracks and crevices appear suddenly or over time. If these aren’t repaired, they provide sites of entry for water straight into your garage. 

Condensation and Humidity
Another form of pesky moisture which can lead to wet garage walls is condensation and humidity inside the space, often due to poor insulation or concrete walls. 

Did you Know?
You can test whether you’ve got a condensation or humidity problem with a small piece of tin foil and a little bit of patience. Tape the foil to your damp garage wall and after a few days, if the water is on the wall side, you know it’s condensation; if the water is on the other side, you’ve got some humidity issues to deal with.

Other common reasons for wet garage walls are:

  • Clogged gutters blocking drains 
  • A driveway sloping towards the garage door 
  • Expansion gaps between slabs that need filling 

How To Stop The Walls Of My Garage Getting Wet

Leaving wet garage walls to worsen is a one-way ticket to hazardous mould and moisture that can cause health problems as well as rusting tools, rotting wood, comprising the structure of your home, reducing its value, and destroying your belongings.

So it’s important to address water on garage walls and here are some ways we would recommend doing it:

  • Install a weather seal onto your garage door
  • Make sure to keep your drains clear of any blockage 
  • Repair any cracks or damage as soon as you notice the issue 
  • Consider concrete sealant or waterproof paint as an extra safety measure
  • Tanking slurry - a mixture of concretes, aggregates, acrylic polymers, and chemical modifiers, which combine to prevent the ingress of water. This can be bought pre-mixed or in powder form to mix yourself at home. 

You May Also Like: How to use tanking slurry to waterproof a garage 

As the old adage goes, prevention is always way better than cure, so rather than having to find a way to remedy a damp and mouldy garage further down the line, it’s always a good idea to put some damage control measures in place ahead of time.

If you’re reading this article because the walls of your garage are already wet, we appreciate prevention isn’t the answer you’re looking for right now. But for those who haven’t yet fallen victim to a soggy garage, take heed of our advice to stay warm, dry and free of mould.

For those who are dealing with damp garage walls, we hope this advice has been helpful to you.

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