Poured concrete foundations crack for a number of reasons. We recently published an article explaining why. This post will examine the different types of crack repair options available. Each method has its pros and cons.
Before we get caught up in the details of how to fix a crack, let’s take a step back for a moment. Foundation crack repair should be done by a professional basement waterproofing company - no ifs, ands or buts. Handymen and plumbers are not usually qualified for the job. You know what? Waterproofers have no business hanging drywall or installing hot water tanks! It really comes down to the experience and expertise of the company that will stand behind the repair.
Cracks can be sealed from either the interior or exterior of the foundation. If done right, either way is equally effective. If there’s a deck or patio in the way, or your basement is unfinished, it’s more common to seal cracks from the interior. If there’s drywall or paneling up, or an obstruction such as a furnace, an exterior method is often preferred.
Before the advent of crack injection, the most common way to seal a crack was to “chip it out and patch it”. What that meant was to take a rotary chipping hammer, chisel out the concrete at the crack location in a “V” shape a few inches deep and then patch it with hydraulic cement. This usually didn’t hold up very long because the crack wasn’t filled all the way to the outside soil. To make matters worse, hydraulic cement is not a very strong or durable product.
Crack injection is now the preferred method of interior foundation crack repair. You might have heard of “Epoxy Injection” or “Urethane Injection”. The process consists of sealing the crack on its inside face with an Epoxy paste and injecting a resin (Epoxy or Urethane) which fills the entire crack all the way to the outside soil. We typically prefer using Urethanes because they remain flexible and are considered by most to be more effective for waterproofing. We used epoxies years ago, but found they were better suited for structural problems.
Some homeowners still believe the best way to fix a foundation wall crack is from the exterior. I’ve found many are from an older generation, before crack injection was brought to the market. Repairing cracks from the exterior is still a great way to go, especially when compared to a hydraulic cement patch on the exterior.
In order to properly seal a crack, the earth must be removed along the wall to expose the crack from the top of the wall all the way down to the footing. Some companies will take out a shovel, and dig a hole big enough to get a man inside it. We prefer using a post hole digger – which is a tool most commonly used to dig fence posts. The hole we core is typically about 8 to 12 inches in diameter. It is a much less disruptive process to your landscaping. We never saw the point in making a three foot wide hole to seal a crack which is typically not much wider than a quarter inch. Once the crack is fully exposed from top to bottom, the hole is filled with granular clay which forms an impermeable water barrier.
Again, we really like to stress that both interior and exterior crack repair solutions are viable options. It really comes down to the obstructions.
We speak from experience; we’ve probably repaired more foundation cracks than anyone in the country. If you have a crack that is leaking, give us a call, or better yet schedule your consultation online and save 10%. Or pose your question below. We love chatting about cracks.