How to Waterproof a Basement — And How to Keep It That Way

Have a basement that’s prone to flooding? Or worse, have a basement that has damage from a bad flood? We hear you. Exterior basement waterproofing can be a powerful tool in keeping your space dry and keeping it that way. Plus, it helps mitigate damage to any items you may have in storage, your furniture, and even your health — did you know that damp areas can cause different types of algae and mildew? Follow along as we provide our guide on how to waterproof a basement in an effective way that doesn’t break the bank.

Getting Started

To start, it’s important to go back to the basics. According to Bob Vila, it’s essential to find out where the source of the water is before prescribing a solution. For example, take a look at the concrete in your basement and on the exterior of your home to see if there are any cracks. If larger areas are wet, you may need to conduct a condensation test. Either way, make sure you nail down the root of the issue before exploring remedies.

How-To: Condensation Test

  • Dry an area of the wall with a rag
  • Attach a square piece of aluminum foil to the wall with tape
  • Peel off the foil after 24 hours
  • Check if the foil feels wet
  • If it’s wet, water is seeping in from outside.
  • If it’s dry, it’s coming from somewhere in the basement.

Fix & Repair

The second step in knowing how to properly waterproof a basement is to repair any current damages. After all, there’s no use in putting a bandaid on a bigger issue. If you have larger foundational red flags that are causing leaks and flooding, call a professional to get that taken care of, and check out our blog for more information on the topic. Or, seal the interior walls with a high-quality waterproof paint if your surfaces pass the condensation test. Lastly, if you just have small cracks that are inviting smaller leaks, fill them with hydraulic cement to resolve the problem.

Prevent & Maintain

Now that you’ve taken care of the big problem, you should consider ways you can stop it from happening again. First, take steps to keep water away from your basement. For example, you can remove foundation planting that requires a lot of watering. Or, you may need to schedule a routine gutter cleaning to ensure the downspouts and drainage system aren’t clogged and expelling runoff properly. And last but not least, look into installing an exterior basement waterproofing system like a waterproofing membrane. According to U.S. Waterproofing, an exterior foundation waterproofing membrane is a barrier for below ground application that becomes a seamless unit to shield against water intrusion. This option may be a little pricey, but it’s definitely a worthwhile investment that protects your home.

Knowing how to waterproof a basement can be overwhelming and frustrating, especially if you’re experiencing issues and you can’t seem to find where the water is coming from. If you feel like you’re at a loss, we always recommend calling an expert for their opinion. And, if you feel like it’s something you can diagnose yourself, be sure to follow this path forward. If you’re having other issues related to moisture and water around your home, be sure to read our blog about how to remove algae on your roof, and how to detect and prevent dry rot

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