How to Waterproof a Basement from Outside

You can recognize the smell of a damp or leaky basement; you might describe it as musty, unpleasant, or moldy. Water leaking into a basement from outside can cause a range of issues, from mold growth to structural damage, and in order to prevent this type of damage, you’ll need to waterproof the basement.

In this guide, we’ll go over how to waterproof a basement from outside (the exterior basement walls), starting with the foundation. You can also waterproof the interior basement walls, which we’ll cover in a separate post.

Repair Cracks in the Foundation

Often—but not always—you can see the cracks and gaps in the foundation that are letting water into the basement. Without repairing the concrete, you won’t be able to waterproof the basement from the outside, and your efforts will literally be washed away as water continues to infiltrate the area.

If you do see cracks or crumbling, consult a professional to assess and address the damage. Simply looking at it won’t tell you what you need to know, as the damage can be more significant than it looks. A professional inspection can help you determine what the issues are and how to resolve them.

Use High-Quality Sealants and Waterproof Membranes

Some cracks can be repaired with injectable sealants, while in other cases, you’ll need industrial-strength sealing of the walls, which is part of wall stabilization.

Waterproof membranes can also be added. These can be applied either from the inside or outside, depending on the specific needs of the foundation walls.

Water follows the path of least resistance. Where you’re seeing water coming into the basement might not be where the cracks are. Consequently, you might be surprised by where the sealant needs to go, as the water might not be coming straight in.

This is another reason a professional foundation inspection is the best option, as you’ll know exactly what you’re dealing with.

Check Your Gutters and Downspouts

Once the foundation is repaired and any cracks have been filled or sealed, it’s time to make sure there’s no water ponding around it. If they’re working properly, your gutters and downspouts direct rainwater away from your foundation.

The gutters need to be clean and free from debris, and the downspouts can be extended so they’re discharging the water several feet away from the base of your house. This will reduce the amount of water that’s in the vicinity, which, in turn, will help keep your basement dry.

Check Your Landscape’s Grading

One reason water can collect around your home’s foundation is poor grading. The surrounding soil and landscaping should gradually slope down away from the house. This will allow water to run downhill rather than running into your foundation (and down your basement walls).

Over time, it’s common for the grading to become compromised and for water to start to accumulate. Keep an eye on this throughout the year. Depending on your specific climate, you might have a wet season in the summer, the winter, or both.

After heavy rainfalls or when there’s a lot of snow melting, check to see if water is accumulating against the foundation. If it is, add dirt in the low areas to divert the water away from the home. You’ll need to check it after subsequent rains and add more as needed until you have the grading right.

Consider French Drains

If altering the grading isn’t working to keep water away from your foundation, exterior French drains might be a good option. These are pipes with perforations that are installed in trenches along the perimeter of the foundation.

Water collects in the pipe and is diverted away from the home, often to an area filled with gravel or crushed stone, which promotes better drainage and helps to prevent clogs.

French drains are a versatile option, and they can be installed inside or outside the basement. They can also prevent soil erosion since the water flows smoothly rather than pooling in one specific location.

Final Thoughts

If you’re getting water in your basement, there are a few things you can do yourself, like repairing or unclogging your gutters, extending your downspouts, and grading your landscaping.

A professional company, like Erie Home, is better equipped to manage foundation repairs, waterproofing and sealing, and determining whether drains should be used. We can even help with any air quality issues you might be having, and our basement waterproofing work is backed by a 25-year warranty.

Talk to your Erie Home professional today to learn more and to schedule a free inspection.

Frequently Asked Questions

What’s the best way to waterproof a basement?

This will depend on what the specific issue is and exactly how the water is getting in. Epoxy, cement repair, polyurethane sealers, exterior drains, and sump pumps all have their place. So does encapsulation, making changes to your property, and installing interior drains. At Erie Home, we have both the tools and the expertise to advise you on the best options for waterproofing your basement.

Is it better to waterproof a basement from the inside or outside?

It depends on your current basement setup and where the leaks are originating from. Interior basement waterproofing can be less disruptive, and it also typically costs less than exterior basement waterproofing.

There are effective techniques for both interior and exterior basement waterproofing. In some cases, a combination of interior and exterior basement waterproofing methods is best.

Can you waterproof a basement by yourself?

It’s possible, if you have the skills, tools, time, and experience. Since a leaky or wet basement can lead to structural damage, mold, and other potentially serious complications, it’s safer to have a professional inspect the foundation and do the work for you. Contact Erie Home for a free inspection and estimate.

Why is my basement leaking after heavy rain?

Cracks and gaps in the foundation walls often cause basement leaking following heavy rain. Sometimes the water can rise up from cracks in the basement floor after heavy rainfall.

How long does basement waterproofing last?

Basement waterproofing should last at least 10 years. Working with a reputable professional contractor is the best way to ensure your basement waterproofing investment will last. For instance, Erie Home’s basement waterproofing services are backed by a 25-year warranty.