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Would you be surprised to learn that one of the most effective ways to prevent basement flooding is with a simple piece of guttering known as a downspout extender? For many homes, this additional section added onto their gutter system lengthens the downspout enough to provide the perfect solution to chronically damp basements and crawl spaces and the musty smells in these areas. By simply diverting water drainage farther away from your home’s foundation, you too can spare yourself the cost of a waterproofing system or other expensive solution.

How Far to Extend the Downspout

To determine how far you should extend your downspout, consider the type of soil present and the slope of the land around your house. If there’s mainly loose, sandy soil where the builders filled in after completing construction and the surface slopes toward the house, water will flow easily through the soil and pool around the foundation, which could cause the structure to settle unevenly.

If you notice that rainwater doesn’t flow away from your house during heavy rainstorms, it’s time to take matters into your own hands by attaching a rigid or flexible extension – which can be found at most home improvement stores – to the end of the gutter downspout. Where there are basement walls, the National Association of Waterproofing and Structural Repair Contractors recommends that the water drain a distance of at least three feet (but preferably six feet) away from basement walls. On sloped land with clay-rich soil, downspouts should extend at least three feet out from the foundation. On flat land, the Association recommends 10 feet, unless the soil is very sandy, in which case the extender may need to be much longer.

Don’t Forget a Splash Block

If your downspout already extends a sufficient length from the house, be sure that there’s a plastic or concrete splash block underneath it to prevent water from eroding a hole in the soil next to the house. A splash block will also help direct water farther away from the foundation.

Prevent Gutter Blockage With a Gutter Helmet® System

Stay tuned for our next blog about improving the curb appeal of downspout extenders. For information on the best rain gutter system and to learn how gutter covers can improve your system, give Gutter Helmet a call today at (800) 824-3772 or contact us online.