Cracks in a window corner

Cracks in the corner of windows or under your windows are a very common occurrence in a home’s walls. They can even form very shortly after the construction of your wall. Before having the cracks under your windows repaired, the source of the cracks and their characteristics must be determined to make sure they won’t reappear.

How do cracks form under windows?

Where do cracks usually appear under windows?

Finding a crack in a window corner is not uncommon. In general, it will appear in the upper part of the window and, in 50% of cases, another will form in the lower part.

The most common cracks under your windows are shrinkage cracks, which are often vertical and appear a few months after constructing your foundation. As concrete dries, it shrinks and begins to crack, usually under your windows. Noticing shrinkage cracks in foundations is commonplace.

Foundation cracks under windows

Concrete foundations with windows tend to develop cracks in specific areas. Essentially, each window decreases the strength of the concrete and creates a gap in the foundation, making it more vulnerable.

The danger here is that any foundation crack can let in moisture or water leaks. This problem can worsen and pose a serious risk for your structure.

Outside of your foundation wall, you may discover that it is covered with plaster. The plaster sometimes displays many more cracks than your foundations actually contain under the windows. To find out if there is a real crack, you have to dig into the plaster and check that the crack does not continue below ground level.

Our expertise at your service

You will be able to benefit from all the expertise of the Crack Expert Group and see all the difference in quality existing on our repairs! For any questions or repairs to cracks in your home, contact one of our experienced technicians from Groupe Fissure Expert inc..

How should you repair the cracks under your windows?

To repair a crack in a window corner, our team of experts uses the technique of high pressure flexible polyurethane injection or the installation of an elastomeric waterproofing membrane.

High pressure flexible polyurethane injection

First, we drill holes along the crack at 4 to 6 inches (10 to 15 cm) at a 45-degree angle to join the crack in the middle of the foundation wall. We then clean the holes and the crack. Next, we seal the crack on the surface with an epoxy plaster. We then insert mechanical metal injection ports into each of the holes. Finally, we inject the flexible polyurethane at high pressure all along the crack from bottom to top.

Installation of an elastomeric waterproofing membrane

To install a waterproofing membrane, we first clean and prepare the surface crack before sealing it with various high-performance polymer sealants. We then apply the primer on the foundation to receive the waterproofing membrane and we finish by laying the elastomeric membrane before sealing the edge of the membrane with an elastomeric bitumen.

The Foundation Crack Expert Group longevity guarantee

At Foundation Crack Expert Group, we are committed to providing you with the best possible expertise to meet your needs while ensuring a lasting, respectful and courteous client relationship.

We also offer you a transferable 10-YEAR GUARANTEE* IN WRITING.

To avoid problems with the cracks under your windows and be guaranteed a comprehensive, fast and long-lasting repair, contact one of our technicians as soon as possible. Only Foundation Crack Expert Group can guarantee repairs that stand the test of time.

(*) Certain restrictions apply