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Ask Mr. Crawlspace

How do I fix water problems in my crawl space that are coming from the outside?

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Water coming in from outside is a hassle that needs to addressed in a hurry. Let’s take a look at common culprits and solutions.

Start with gutters and downspouts

Clogged gutters and misdirected downspouts do little to protect your home from water. If you have water problems in your crawlspace, this is a good place to begin your detective work. Gutters should be cleaned twice yearly at a minimum. When gutters are clogged with debris, leaves or ice, water has no place to go but into your home. Likewise, downspouts must be securely fastened and directed away from the home (about 20 feet is ideal) so that water flow doesn’t seep inside.

Check grading

The slope of the area surrounding your home will determine the direction of water flow. During the next heavy rain, grab an umbrella and head outside to watch which way the water travels. Options to interrupt water flow in the direction of your home include:

  • French drains – this option directs water away from your home using a gravel filled trench and piping.
  • Landscape design – strategically place cobblestones or rocks in affected areas so that the flow of water is directed away from your foundation.
  • Extend drain lines – if you notice that your sump pump is working overtime and you still have water invasion or that your lawn feel more like marshland, you may need to have the drain lines from your sump pump or downspouts extended.
  • Mulch – be sure to leave a gap between your mulch and siding. Material that is allowed too close to the home will absorb moisture and release it into your foundation when it becomes oversaturated.

Look for leaks

Don’t stop your detective work outdoors. Get into the crawl space if you can and shine a light over every crack and crevice. The water may be entering through a leak in the walls or crack in the floor. Also check any drains to be sure there are no clogs.

Water in your crawl space must be addressed immediately. Left untreated, this water will cause worsening problems, including damage to your foundation, problems with pests, poor air quality mold and wood decay. Begin with the basics, such as your gutters, and call in professional help if the problem continues.

In many cases, water appears in the crawl space only during periods of heavy rain, or it enters the crawl space even though there are no issues with grading or downspouts. In these case, it is best to install a French drain around the inside perimeter walls of the crawl space and terminate into a sump pump at the lowest point of the crawl. The sump pump is installed so that will pump the water outside of the crawl space and away from the house. This is an ideal solution for intermittent water problems: when water enters the crawl space it drains into the sump pump and is automatically pumped out.

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