Due to the brittle nature of exterior (or interior) concrete when subjected to strong traction, it is not uncommon to see cracks appear. This normal phenomenon in the life cycle of a structure is not synonymous with a design defect. Ground movements due to the action of frost or water are usually the cause.
In order to achieve an adequate crack seal, a number of criteria such as the type of surface come into play. In the context of concrete foundations, selecting the wrong product can lead to serious problems. The choice of the type of sealant also follows from the method envisaged. The repair can be carried out from inside the building or from the outside depending on the extent of the crack.
Choice of sealant for the repair of a concrete crack from the inside
Faster to implement, this repair technique has many advantages. Consisting of a high-pressure injection of resin into the crack, it is the most economical and least restrictive solution. It is carried out in all conditions and makes it possible to use an effective sealant to seal a more or less narrow concrete crack.
Polyurethane foam
Offering great flexibility, polyurethane is an ideal sealing element for the residential sector. Its high pressure injection is carried out from the inside in all seasons and even in case of water infiltration. Depending on the thickness of the wall, the polyurethane foam penetrates and adapts to the shape of the crack, taking advantage of an expansion of seven times its initial volume. This quick-setting concrete crack sealant is distinguished by elastic properties and relatively low cost.
Epoxy resin
Acting as a weld, epoxy is highly effective due to its powerful action. Like a glue, it seeps into the crack to harden in three or four hours. Ideally intended for large buildings, an interior repair with epoxy resin limits new movements due to the vagaries of the weather. Using it as a sealant to repair a concrete crack is more expensive than polyurethane foam, but allows the structure to regain its full strength. However, it is not recommended in a humid environment prone to infiltration.
A sealant suitable for repairing an exterior concrete crack
In the event that the crack is too large, it is better to proceed from outside the building. Excavation work is therefore necessary to reach the affected area. Once the latter is cleaned, an opening in the outer crack is made in a V-shape to apply the cement. The selected sealant is then used to fill the concrete crack, before covering the whole with a waterproofing membrane. A very reliable solution, but much more expensive than intervening from within.
Seek help from a specialist to make sure you’re using the right sealant
When choosing the sealant to caulk a concrete crack, it is therefore necessary to study its characteristics. A specialist will be able to select the most suitable method and the corresponding product.
At Groupe Fissure Expert, we have solid experience in the field of foundation crack repair, particularly for everything related to exterior concrete. Do not hesitate to let us know more details about your situation through our free quote form, in order to benefit from personalized support.
Need a Crack Repair Expert?
If you notice cracks on your foundation, it is important to act quickly. Fissure Expert offers professional foundation crack injection services throughout Quebec. Call a certified foundation crack contractor for a free estimate. We serve Trois-Rivières, Chicoutimi, Laval and many other cities.