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How to Find and Fix a Foundation Leak

If you’re like most homeowners, finding and fixing a foundation leak is probably the last thing you want to do—but it’s definitely not something you want to ignore. A neglected foundation leak can eventually cause significant structural damage, which means a costly repair. Therefore, if you want to protect your investment, you’ll need to know how to find and fix a foundation leak. In this article, we’ll review the causes of foundation leaks, how to find them, and possible solutions you can implement.

What Causes a Foundation Wall to Leak?

Foundation walls can leak for various reasons. However, the top three are hydrostatic pressure, shrinkage cracks, and leaks through the cove joint. In some cases, more than one of these together may be causing the leak. 

Leaks caused by hydrostatic pressure

Poor drainage in the ground around the foundation can cause hydrostatic pressure to build up and push against the foundation wall. If the pressure isn’t relieved, it can cause a foundation wall to bow inward, and even crack. Hydrostatic pressure is strong enough to push water through invisible cracks in a foundation wall and into your basement or crawl space. 

Leaks caused by shrinkage cracks

Shrinkage cracks (which are very common) are caused by the natural drying and curing process of concrete. While they don’t immediately threaten your home’s structural integrity, they can allow water to enter a basement or crawl space—especially if poor drainage has caused hydrostatic pressure to build up in the ground outside the foundation wall. 

Leaks through the cove joint

The cove joint is where the foundation wall meets the basement floor, and is a prime spot for water to enter your home. Over time, the sealant in this joint can deteriorate, allowing water to flow through and enter your basement. If hydrostatic pressure has built up in the soil around the foundation, it can push water through the cove joint and into the basement. 

How to Find a Leak in a Foundation Wall

If you’re worried about a potential leak in your foundation wall, there are several things you can do to find out for sure whether there’s a leak:

  • Keep an eye out for any signs of efflorescence—a white, powdery substance which can form on concrete surfaces that have been in contact with water. Efflorescence is a big indicator that there’s moisture seeping through your foundation.
  • Another thing to look for is leaks through the cove joint, which (as noted above) is the spot where the floor and wall meet. If you notice any water seeping in through there, it’s a clear sign that you’ve got a problem. 
  • Test for foundation wall leaks by spraying water against the wall for a few minutes. If you notice any water seeping through, you’ve definitely got a leak. 
  • If you’ve got carpet in your basement, check the tack strip for signs of water damage
  • Always be on the lookout for visible mold or mildew, which could indicate a leak or excess moisture.
  • Check your pipes for any signs of leaks. Signs can include a decrease in water pressure, a water bill that’s higher than expected, a water heater that’s constantly running, etc.

How to Fix a Leak in a Foundation Wall

Foundation wall leaks can be repaired in multiple ways, including the following:

  • Waterproof the wall – This involves applying a specialized coating to the exterior of the wall to prevent water from seeping through. It’s important to ensure the coating is applied thoroughly and properly to guarantee maximum efficacy. 
  • Install a drain tile system – This involves excavating around the outside perimeter of the foundation down to the footing level and digging a shallow trench. After the trench is lined with gravel, a perforated drainage pipe is placed and then covered with more gravel. Finally, the excavated soil is replaced. Now, any excess groundwater will be directed away from the foundation. An interior drain tile system can also be installed under the basement floor or in a crawl space. 
  • Use downspout extensions – Downspout extensions are long, flexible tubes that attach to your downspouts and direct water away from the foundation. 
  • Clean your gutters regularly – It’s also essential to clean your gutters regularly to prevent them from becoming clogged. You want water flowing into the downspouts, not spilling over the side of the house and soaking the ground around the foundation. 
  • Regrade your yard – Your yard should slope away from the foundation. This will prevent groundwater from draining toward the foundation wall. 

Note that most of the above involves making sure water can’t collect in the ground around the foundation. If the ground around your foundation is dry, you don’t need to lose sleep worrying about a foundation leak.

If you think your foundation might have a leak, contact BQ Basements and Concrete today to schedule a foundation evaluation. If we find a leak, we’ll provide you with a repair estimate. 

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