Criteria For Drainage

Foundation Drainage

• A proper foundation drain system is installed directly next to the footings. It is buried in several feet of gravel and is sloped slightly toward the sump pit. The water travels through these pipes to the sump pit in the basement and is then pumped away from the home. Modern construction uses 4-inch perforated corrugated pipe for this job. It is an inexpensive material and is easy to install.

Gutter and Downspout Drainage

• Your home's roof collects a surprising amount of water. This water travels down the shingle surface to the gutter system installed on the fascia. It then flows downhill to the downspout system, where it is discharged onto the grade. The downspouts should terminate at least 4 feet from the foundation in a location where the water will naturally flow away from the house. You may need to extend the downspouts for 10 to 20 feet before the lot grade moving in this direction.

Soil Conditions

• The type of ground soil around the building affects the water's ability to peculate back into the soil. Gravel, sand and rock allow the water to penetrate the ground quickly. Hard clay or soil with high organic content have the opposite effect. They can hold the water in place, giving it an opportunity to travel back to the home.

French Drain

• A French drain is a good location to discharge drainage water. It is a large hole in the ground filled with gravel. It gives the excess water the surface area it needs to safely reenter the soil. The size of French drain you need depends on the area of the roof, the amount of rainfall during the wettest time of the year and the soil conditions. French drains should be installed at least 20 to 30 feet away from the home to assure water doesn't travel back.