Protect Your Basement Against Rain & Ground Water Flooding
GROUND WATER AND YOUR HOME
In Nebraska, heavy rains can result in water damage that ranges from stale odors to flooded basements and crawlspaces. Over time, chronic or repeated moisture exposure due to water intrusion will damage most building components. In addition to deteriorating building materials, mold growth is the inevitable outcome.
Prevention is the key to basement flooding caused by ground water. I’ve seen thousands of flooded basements over the past twenty years and a few basic precautions can make the difference between a wet and dry basement. The further away you get the rain water from your roof away from your foundation, the better.
Did you know that a 1,200 square foot roof (smaller than average roof) collects 748 gallons of water with just 1” of rainfall. In Nebraska, a 2” - 3” rainfall or more is very common. So that same 1,200 square foot roof now collects 2,244 gallons of water during a 3” rainfall. Divide that 2,244 gallons of water by four downspouts and you have 561 gallons per downspout! That is a lot of water to be dumping out just a few feet from your foundation. If you have a standard 36” downspout extension, you may very well have water damage to your basement.
Worse yet, your basement doesn’t have to even “flood” to sustain damage. Some of the worst type of water damage results from very small, almost imperceptable amounts of water leaking through your foundation. Long-term exposure to small amounts of water eventually leads to black mold growth in a finished basement. One gallon of of 561 gallons seeping into your finished drywall can cause a surprising amount of mold growth.
So what can you do? Even if you don’t have a drain tile and sump pump system, there’s hope. Fortunately, drain tile is your last line of defense. Follow these few basic guidelines and your chances of avoiding a flooded basement and days of water damage cleanup improve dramatically.
1. Keep your gutters clean; even a small amount of debris at the downspout can cause your gutters to cascade over. Depending on where you live in Nebraska, your neighbor’s house could be close enough that their gutters direct water toward your foundation. After you’ve verified that your gutters are working properly, take a quick look at the house next door to avoid a flooded basement.
2. Downspouts should be properly sized to handle the volume of water and the extensions should be as long as possible to get the water far from the foundation. This is probably the main cause that I see for a flooded basement caused by rain water. If the downspout is missing, loose or simply too short, it can make the difference between rain water flooding your basement or not. Always keep the downspout extensions in good working order.
3. The grading should be positively graded away from the house. Low areas, depressions and window wells can allow water to be diverted back toward the foundation. If rain water is flowing towards your foundation, you’re going to have a wet basement.
4. If you have a sump pump and drain tile system, perodically check your pump to verify it’s functioning properly. Your drain tile and sump pump system is really your last line of defense against a flooded basement. Ground water will accumulate at your foundation wall so it’s critical that your sump pump is working properly. If your sump pump fails, ground water will find its way into your basement.