Rainwater Seeping Through Your Walls? Here's What to Do

Rain hammers your roof. Wind rattles the windows. You notice a dark, damp patch spreading across your living room wall. Water’s seeping through your wall. What do you do?

Heavy storms can push rain into surprising nooks and crannies on the outside of your home. Once the water finds a way in, it can keep going until it starts seeping through your walls. Don’t let this surprise paralyze you. By acting quickly and bringing in a team experienced in storm repair services, you can limit the damage and help protect your home and wallet.

Key Takeaways

• Heavy rain can force water through cracks, gaps, and worn spots in your walls, especially during storms with strong winds.
• When rainwater seeps through walls, it can leave stains, peeling paint, weakened drywalls, and even mold if you don’t catch it soon enough.
• Act quickly to dry the area and find the source of the leak to help limit the damage.
• You can prevent future rainwater leaks with simple fixes like sealing cracks and cleaning your gutters.
• If you have bigger leaks or a lot of water damage, contact SERVPRO for professional water remediation.

Why Does Rainwater Seep Through Walls?

Your house is supposed to be your fortress, but over time, hairline cracks or small gaps can form in your home’s exterior. While you might never notice these minor blemishes, a windy storm can drive rainwater through the small openings.

Common causes are the most likely culprits of a rain leak in your walls. By noting where the water shows up, you may be able to zero in on the main problem.

Cracks in Masonry and the Foundation

Brick, block, and concrete look tough, but they’re not invincible. As your house settles over the years, the ground beneath it shifts. That movement puts stress on your foundation and exterior walls. This stress can show up as small cracks. During a long storm, rain can work its way through these cracks and into your home. The problem can get worse over time as water freezes and expands in the colder months.

Failed Caulk or Sealant Around Windows and Doors

Caulk and sealant around your windows and doorframes create a barrier from the surrounding wall. But caulk and sealant don’t last forever. The sun, big temperature swings, and age can cause these materials to dry out, shrink, and eventually crack. Once that seal breaks, water has a direct path to slip through. This often shows up as a rainwater leak on your wall right next to a window or door frame.

Poor Exterior Drainage and Grading

Ideally, the ground around your home should slope away from the foundation so rainwater runs away from your house. But if the grading is off, water can pool next to your foundation. That standing water puts constant pressure on your walls and eventually finds its way through cracks, gaps, or porous materials.

Watch for stains that stretch along the bottom of a wall on the side of your house that faces low or flat ground.

Blocked or Missing Weep Holes

Water weep holes are small, easy-to-miss gaps built into the base of brick walls. Their job is to let moisture that gets trapped behind the brick escape before it causes damage. When dirt, debris, mulch, or even a fresh coat of paint blocks the holes, water has nowhere to go. Instead of draining out, water gets pushed further into your wall.

Since weep holes sit near the ground, look for a stain that forms low on a brick wall.

The Damage Rainwater Seeping Through Walls Can Cause

That damp patch on your wall might seem relatively minor, but looks can be deceiving. Once rainwater gets into a wall cavity, it can soak insulation, warp drywall, and ruin your paint or wallpaper. And the longer the water sits, the more trouble it causes.

Mold just needs moisture, warmth, and around 24 to 72 hours to start growing. Inside your walls, mold can bloom out of sight until the smell or discolorations give it away. Don’t let mold fester. It can trigger coughing, skin irritation, or allergic reactions.

When wood framing, drywall, and insulation stay wet, they begin to degrade and lose strength. Over time, this can lead to sagging walls, weakened support, and even wood rot that spreads beyond the original rain leak.

What to Do When Rain Is Seeping Through Your Walls

The moment you spot water coming through a wall, it’s time to take action. Here’s how to handle it, both while the storm is happening and once it passes.

During and Immediately After Rain

The storm is still raging, and water is weeping down your walls, but you don’t have time to gape at the damage. Here’s what to do:

• Move your furniture and belongings away from the wet wall so they don’t get soaked.
• Place towels or a bucket near the leak to catch the water and protect your floors.
• Snap a few photos of the affected area. You’ll want these for insurance later.
• If the wet area of your wall is anywhere near an outlet, turn off electricity to those outlets or fixtures.

Dry Out and Assess the Damage

Once the rain stops, bring in fans and a dehumidifier to start drying things out. This is also a good time to try and figure out how deep the moisture goes. Is it just sitting on the surface of your wall, or has it soaked throughout the wall cavity? This makes a big difference.

You might be able to handle a minor surface issue on your own. But if there’s a lot of moisture inside your wall, that usually means it’s time to call in a pro. Either way, knowing how to fix a wall leaking from rainwater starts with understanding exactly what you’re dealing with.

How to Fix and Prevent Rain Seeping Through Walls

Ready to roll up your sleeves and fix your wet wall? Hold on. Some fixes are simple enough that you can tackle them yourself. Others, however, call for a professional.

Homeowner Friendly Fixes

What you can do on your own to help prevent future rainwater leaks:

• Clear out your gutters, so rain flows away from your home instead of spilling over.
• Extend your downspouts a few extra feet so water drains farther from your foundation.
• Re-grade the soil near your foundation so it slopes away from the house, not toward it.
• Re-caulk around windows and doors where old sealant has cracked or pulled away.

When You Need a Professional

If the damage to your home is more than a surface-level issue, it’s usually a good idea to bring in a restoration professional. Here’s what a specialist can do:

• Seal any exterior water penetrations where pipes, vents, or wires pass through your walls.
• Re-point deteriorated mortar joints in brick or block walls.
• Apply a breathable masonry waterproofing sealer to protect porous exterior walls.

If you’re wondering how to fix a leaking wall from rainwater, it’s often worth calling someone with the right tools and training to do the repair correctly.

How SERVPRO Can Help

If you notice a musty smell near your wet wall, if the drywall feels soft or spongy, or if the leak returns every time it rains, you need to bring in a pro. SERVPRO technicians can make a big difference in handling water seeping through your wall.

We'll bring specialized equipment to the job, like moisture meters that track exactly how far the water has seeped through your walls. We also use commercial-grade drying equipment and mold remediation treatments to get the job done right.

Find your local SERVPRO today. 

FAQs

Why Is Rainwater Seeping Through My Walls?

Rain usually gets in through cracks in masonry, failed caulk around windows and doors, poor exterior drainage, or blocked water weeping holes. Storms with heavy wind push water into these weak spots, forcing it through gaps that stay dry under normal conditions.

How Do You Fix a Leaking Wall from Rainwater?

Start by finding the entry point of the water, then seal cracks, re-caulk windows and doors, clear gutters, or improve drainage as needed. If moisture has reached the wall cavity or caused structural damage, it’s a good idea to request a professional assessment.

Can Rain Seeping Through Walls Cause Mold?

Yes. Mold can begin growing within 24 to 72 hours once moisture gets trapped inside a wall. Because it often grows out of sight, your first clue that mold is in your walls could be a musty smell or discolored stains.

Is Water Seeping Through Walls Covered by Insurance?

The answer depends on your policy and the cause of the leak. Many policies cover sudden, storm-related damage, but they will exclude damage due to long-term neglect. If you aren’t sure what your policy covers, call your insurance agent.