Keeping water away from your home and foundation is essential to maintaining the integrity of the structure. In addition to warping the walls in your basement, drainage problems could also lead to a flooded basement.
One of the most effective methods of an outdoor waterproofing system is to use a sump pump outside your home. Exterior sump pumps will take unwanted pooling rainwater in your backyard and drain it to a location safely away from your foundation. This can be accomplished in one of two ways. First, excess rainwater is collected and then pumped into a storm sewer. Or the excess water can be sent to a safe area of your yard.
Just as with an indoor pressure relief system (PRS), an outdoor sump pump requires a drainage system such as a French drain to be installed on the perimeter of your house. These drains lead the water into the sump pit, and the submersible pump in the pit effectively pumps the water away. The pump requires an electrical source, and perhaps a battery backup for when the power goes out.
If you have a stairwell or window well that fills with water when it rains, an exterior sump pump in these locations may solve the problem of water entering your basement.