Leaking foundation crack repair

In order to properly seal leaking foundation cracks you must first determine the best method of repair to use based on several factors. A poured concrete foundation crack can be repaired either internally (from the inside of your basement) or externally (outside digging). While both approaches can effectively seal your leaking foundation crack, external repairs take longer, cause damage to landscaping, present safety risks and are far more expensive than foundation crack injection repairs.

Although there are some scenarios that would warrant an exterior repair (such as a crack in a concrete block foundation or an inaccessible crack on the interior), more often than not, a foundation leak in a poured concrete foundation is typically repaired internally by using a process known as polyurethane crack injection. This method of repair is effective (when done properly), reliable, cost effective and is typically the least invasive solution to repair just about any poured concrete foundation crack.

Polyurethane crack injections are done at a fraction of the cost and time required for exterior foundation crack repairs. A polyurethane crack injection involves drilling holes perpendicular to the crack (these serve as channels through which materials are injected into the crack) which are then cleaned and fitted with injection packers. Using these channels, the crack is acid flushed and water flushed before polyurethane is injected using a high-pressure pump. Once injected, the polyurethane reacts with the water within the crack and expands throughout its entirety, creating a complete seal of the leaking foundation crack.

Depending on the width of the crack it may be necessary to stabilize the crack to ensure that the crack cannot widen over time. This is accomplished by installing one or more carbon fiber stitches (green horizontal line in the picture below)

Although internal foundation crack repairs are often the cheapest and quickest solution for most homeowners, many basement waterproofing companies typically recommend external repairs, sometimes presenting it as the best or only option. This is because excavation and coating the wall, while more labour intensive, requires little skill or experience as compared to internal polyurethane crack injections which necessitate skilled technicians with specialized training. Secondly, external repairs generate greater profit due to higher pricing and higher margins.

While it is true that both approaches can effectively repair and seal your leaking foundation, we recommend that external excavation only be considered when interior repairs are problematic or impossible. It should be noted that exterior waterproofing repairs tend to suffer from “scope creep”. Here is the logic: “since you are already digging up 6 linear feet, why not do 25 feet or even the whole foundation just in case you get a future leak?” (Obviously this increases the price and profits considerably)

External foundation crack repair involves digging down as far as the foundation footing, repairing the crack, coating the foundation with a liquid or solid rubber membrane (BlueSkin), installing foundation wrap and backfilling.

We offer both interior and exterior foundation crack repairs. Call us today to speak with one of our expert technicians.