The dramatic temperature variations characteristic of Quebec’s climate can often cause concrete to warp. This is why building foundations may start to develop slight imperfections several months, or even a full year, after the concrete was put in place.
Water, one of the main ingredients in concrete, is used to make wet cement more malleable and the end result, more durable. As the concrete dries and hardens, water evaporation leads to a decrease in volume that can alter the appearance of the finished product. This explains why foundation cracks tend to develop during and following the hardening process, which can take as long as 15 months to complete.
Concrete foundation cracks don’t systematically cause problems; some are completely benign. They typically appear near the lower corners of windows and slowly make their way to the base of the foundation. This phenomenon usually isn’t cause for concern, as long as the cracks remain less than 1/8 of an inch (three millimetres) wide. The same rule of thumb applies to cracks in basement floor slabs. That being said, it’s always best to repair cracks before they become problematic.
To fix common concrete fissures, we use specialized equipment—which can generate up to 8,000 lbs. of pressure—to fill the cracks with polyurethane. Indoor repairs can be performed 12 months a year, but temperatures above -5 °C are required to carry out similar work outdoors.
For exterior repairs, we start by excavating the foundation perimeter to reach the footing. We then inject polyurethane into the cracks using the same method employed for indoor repairs. A waterproofing and/or drainage membrane can be installed once the cracks have been filled to keep repel moisture away from the repairs.
Once the issue is fixed, we backfill the excavated area and level the ground to create a two-metre slope around the foundation. This is done to prevent future water infiltration by ensuring all water is efficiently carried away from the property.
We employ a similar method to fill structural cracks using epoxy instead of polyurethane.
We can also fill gaps in foundations by means of a process called cold jointing.
We guarantee our indoor repairs for 10 years and our exterior repairs for 15. This coverage is transferrable to new owners in the event of the property’s sale.