Basement and Crawlspace Flooding

Your basement and crawlspace probably aren’t two places in your home you visit on a regular basis. Why would you? Both spaces are dark, dusty, dank and probably full of cobwebs. In reality, the only times you venture into these caverns are for home repairs or to take out the Christmas decorations. In fact, many homeowners don’t even know where their crawlspace is.

Even though they don’t get much thought, did you know these areas are especially prone to flooding? And, when they do flood, the consequences can be tragic? If you live in a part of the country where flooding is a real danger, or your plumbing system is old, you need to keep an eye on these spaces. In this article, we discuss common signs and causes of basement and crawlspace flooding, as well as preventative measures.

Signs of Basement or Crawlspace Flooding

Because you probably don’t make it a habit to check these areas on a regular basis, there are some signs of potential flooding you can look for.


Mold is nasty and it only needs a couple of conditions to take hold. Moisture and darkness. Your basement and crawlspace satisfy both requirements. If you start to notice mold on hard surfaces like vents or ducts, it’s a sign that there’s moisture somewhere in close proximity.

It’s important to address the problem right away as mold can pose health problems to everyone under your roof. If it gets into your ventilation system, the danger becomes even greater.


Every now and then, take a couple minutes to walk around the perimeter of your home. If you live in a cold region where the ground freezes, this is a must in the spring when the ground thaws. Look for low spots where moisture has gathered next to your foundation. If anything is apparent, you’ll want to check your basement or crawlspace to see if water has seeped inside.

Wet Spots

Not all signs of potential flooding occur outside your home. If you notice any wet spots on your floors, walls or ceilings, you might be looking at a leaky pipe inside your home. In this case, it’s best to check the pipe in the location of the wet spot sooner rather than later. In this case, you might have to crawl inside to look for evidence.

Causes of Basement and Crawlspace Flooding

Bad Downspouts

Downspouts serve the purpose of directing water away from your home and its foundation. If not installed correctly, they serve little to no purpose. As water drains off your roof, it will puddle in low spots next to your home’s foundation. Over time, it’s easy for water to seep into your basement or crawlspace and damage the interior. This is one of the reasons these dark spaces can flood without notice.

Gutter Debris

Just like downspouts, the job of gutters is to divert outside water away from your home. In order to do so, they have to be clean. If you don’t clean your gutters on a regular basis, debris builds up and prevents the flow of water. Eventually, the debris will cause gutters to overflow and water will cascade over the edges, leaving the ground below saturated with water. And, you guessed it, that water has an evil way of finding its way under your foundation.

Water Supply Line, Sump Pump Failure, Hot Water Tank

Within your basement itself, broken water supply lines, sump pump failures and leaky water heater tanks can all cause flooding. Water supply lines are susceptible to leaks if they’re old or freeze. The same is true for sump pumps and hot water tanks. That’s why it’s a good idea to inspect all three annually to make sure they’re in working order.

How to Prevent Basement and Crawlspace Flooding

Now that we’ve covered the signs and causes of basement and crawlspace flooding, let’s look at some preventative measures you can take.

Look for Cracks

As mentioned above, it’s a good idea to routinely inspect the perimeter of your home. If you notice any cracks in your foundation, there’s a good chance water could leak inside. If you notice anything that looks less than sealed off, all you need is some epoxy to remedy the problem.

Sump Pump and Water Tank Maintenance

If you have a sump pump, you’re already ahead of the game in preventing mold and flooding. However, the key is to perform the necessary maintenance. The same goes for your hot water tank. Most maintenance only needs to be done once a year, but it’s something you should keep on top of.


There’s nothing better than having a beautiful yard and garden. You look forward to planting every spring so you can enjoy the fruits of your labor all summer and fall. Keep in mind how you shape your gardens and flower beds though. It’s a good idea to contour them so water runs away from your house, not toward it. If you keep this in mind during the initial stages of planting, you won’t have to worry about water flowing in the wrong direction.

Flooded basements and crawlspaces can be a homeowner’s worst nightmare. In some cases, they can ruin your entire home. If you know the signs to look for and take some preventative measures on the front end, however, you’ll save yourself a potential nightmare and a lot of money down the road.

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