How to Stop Water Coming Through Garage Wall

If you have a garage, then you know that one of the annoying things about it is that water can come through the walls. In this post, we’ll show you how to stop water coming through garage wall. We’ll also give you tips on fixing the problem if it’s already happening. So, keep reading to find out more.

how to stop water coming through garage wall

Summary: If you’re experiencing water coming through your garage wall, addressing it as soon as possible is essential to prevent further damage. Once you’ve identified the source, take action to fix it. This could involve installing a drainage system around the garage, repairing the pipes, or sealing any cracks in the foundation.

What Causes Water to Come Through Garage Walls?

There are a few different things that can cause water to come through your garage walls, including:

Cracks in the Foundation:

If there are cracks in your garage’s foundation, water can seep through them and into your garage. Therefore, it’s important to repair any cracks as soon as possible so they don’t get bigger and cause more damage.

Poor Drainage:

If your garage lacks proper drainage, water can build up around it and seep through the walls. This is especially a problem if you live in an area with heavy rain or snow.


If there are any leaks in your garage, then water can come through those as well. This could be from a leaky roof or pipes. Make sure to fix any leaks as soon as possible.


If your garage is very humid, then that can also cause water to come through the walls. This is because moisture will build up and eventually seep through. Humidity is often caused by not having enough ventilation in your garage.

Pressure Washers:

If you use a pressure washer to clean your garage, then that can also cause water to come through the walls. This is because the pressure from the washer can force water through any cracks or holes.

Step by Step How to Stop Water Coming Through Garage Wall

Step 1: Identify the Source of Water

Before you can effectively stop water from coming through your garage wall, it’s essential to identify the source of the water. Inspect the area carefully to determine if the water is seeping in from the ground, flowing down from the roof, or coming from another external source. Understanding the source will help you choose the appropriate solutions for addressing the problem.

Step 2: Clear Gutters and Downspouts

If the water is coming from the roof and overflowing gutters, it’s crucial to clear out any debris that may be obstructing the flow of water. Clean your gutters and downspouts, removing leaves, twigs, and other debris that could cause water to back up and overflow. Ensure that the downspouts direct water away from the foundation of your garage.

Step 3: Check for Cracks or Gaps

Inspect the exterior of your garage wall for any visible cracks or gaps that could be allowing water to seep through. Pay close attention to areas where the wall meets the foundation or where different materials join together. Even small cracks or gaps can allow water infiltration, so it’s important to address them.

Step 4: Seal Cracks and Gaps

Once you’ve identified cracks or gaps in the garage wall, it’s time to seal them. Use a high-quality exterior caulk or sealant that is specifically designed for outdoor use. Clean the cracks or gaps thoroughly, removing any dirt or loose debris. Apply the caulk or sealant generously, ensuring that it fills the entire gap or crack. Smooth the surface with a putty knife or your finger to create a neat finish.

Step 5: Install a Waterproof Membrane

For added protection against water infiltration, consider installing a waterproof membrane on the exterior of the garage wall. Waterproof membranes create a barrier that prevents water from penetrating the wall. They are available in various forms, such as liquid coatings or sheet membranes. Follow the manufacturer’s instructions for proper installation, ensuring that the entire wall surface is covered.

Step 6: Improve Drainage Around the Garage

If the water is pooling near the garage wall or flowing toward it due to poor drainage, it’s crucial to improve the drainage system. Ensure that the ground slopes away from the garage, directing water away from the structure. You may need to re-grade the area around the garage or install drainage channels or French drains to divert water effectively.

Step 7: Install a Sump Pump

In cases where groundwater is a persistent issue, installing a sump pump can help prevent water from entering the garage. A sump pump is designed to remove water that accumulates in a pit (sump) below the garage floor. It pumps the water out and away from the garage, effectively preventing water from seeping through the walls. Consult a professional for proper installation and ensure regular maintenance of the sump pump system.

Step 8: Consider Waterproofing Paint or Coating

Another option to prevent water from coming through the garage wall is to apply a waterproofing paint or coating. Waterproofing products create a protective barrier that repels water and prevents moisture penetration. Choose a high-quality waterproofing paint or coating designed for use on exterior surfaces. Clean the wall thoroughly and apply the product according to the manufacturer’s instructions.

Step 9: Check Interior Wall Condition

Inspect the interior wall of the garage for any signs of water damage, such as discoloration, mold, or peeling paint. If there are areas of concern, address them promptly to prevent further damage. Repair any damaged drywall or plaster and apply a mold-resistant paint to inhibit mold growth.

Step 10: Install Interior Drainage System (If Needed)

If water continues to infiltrate the garage even 

after taking the above steps, it may be necessary to install an interior drainage system. This is especially true if you have a high water table or frequent water intrusion. An interior drainage system consists of a perforated pipe installed along the base of the garage wall, which collects and redirects water to a sump pump or drainage outlet.

Consult with a professional contractor who specializes in waterproofing to assess the need for an interior drainage system and determine the best approach for your specific situation. They will have the expertise to properly install the drainage system and ensure that it effectively manages water intrusion.

Step 11: Monitor and Maintain

After implementing the necessary measures to stop water from coming through your garage wall, it’s important to regularly monitor and maintain the system. Check for any signs of water infiltration or damage, both on the exterior and interior of the garage. Address any issues promptly to prevent further damage.

Additionally, maintain proper drainage around the garage by regularly cleaning gutters and downspouts, as well as ensuring the surrounding ground slopes away from the structure. Check the operation of any installed sump pumps or interior drainage systems to ensure they are functioning correctly.

In conclusion, stopping water from coming through your garage wall requires a systematic approach to identify the source and implement appropriate solutions. By addressing issues such as gutter overflow, cracks or gaps in the wall, improving drainage, and considering additional measures like waterproofing coatings or interior drainage systems, you can effectively prevent water infiltration. It is crucial to regularly monitor and maintain the systems to ensure their continued effectiveness. If you encounter complex issues or are unsure about the best solutions, it is advisable to consult with professionals who specialize in waterproofing and have the expertise to provide tailored recommendations for your specific situation.

Frequently Asked Questions

How Much Does It Cost to Fix Water Coming Through a Garage Wall?

The cost of fixing water coming through a garage wall will vary depending on the cause of the problem. In most cases, you’ll need to seal the cracks and apply a waterproofing membrane. This can cost anywhere from $500 to $1,000. If you’re having a serious problem, then you may need to install a French drain.

This can cost upwards of $2,000. Hiring a professional to fix the problem can also add to the cost. You’ll most likely need to pay an hourly rate for their services. The average cost of hiring a professional is $50 to $100 per hour.

Can White Cement Stop Water Leakage?

White cement can be used to stop water leakage in some cases. However, it’s not a permanent solution and will need to be reapplied regularly. In most cases, it’s best to use a sealant or another waterproofing method to stop water from leaking through your garage wall.

If you decide to use white cement to stop a water leak, apply it evenly and allow it to dry completely before adding any additional layers. You may also need to reapply the cement after heavy rains or if the water leak is particularly severe.

Is It Better to Seal the Inside or Outside of a Garage Wall?

It’s usually best to seal the inside of a garage wall. This is because the inside of a garage wall is typically drier than the outside. Unfortunately, sealing the outside of a garage wall can trap moisture inside, leading to more serious problems like mold and mildew. If you seal the outside of your garage wall, be sure to use a breathable sealant that will allow any moisture trapped inside to escape.

Applying a Waterproofing  Membrane


This article has presented a few different options for how to stop water coming through garage wall. So, there you have it. A few ways that you can control the water coming through your garage wall. All of these solutions are relatively easy and inexpensive to do. And, if you follow our tips, you should see a noticeable difference in the amount of water making its way into your garage. Have any questions or comments? Let us know in the comments section below.

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Rick Kelly

I am Rick. I grew up helping my dad with his handyman service. I learned a lot from him about how to fix things, and also about how to work hard and take care of business. These days, I'm still into fixing things- only now, I'm doing it for a living. I'm always looking for new ways to help people grow and develop. That's why I have created this blog to share all my experience and knowledge so that I can help people who are interested in DIY repair.

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