Drainage and Grading

Drainage and Grading photos: P 157, P 170

The soil next to the foundation should slope away from the house to prevent any rainwater from building up next to the foundation. Usually the soil only needs to slope 1/2 inch for every foot away from the house to properly drain the water accumulations. All bushes, shrubs and trees should be pruned away from the side of the house. This will allow enough sunlight and air next to the foundation to help prevent rot and wood destroying insect problems.

If the house is located at the base of a hill there should be a catch basin o prevent water problems. These are large concrete underground drains. You also may find a large dip in the soil that looks like a long, narrow trench for water drainage. These dug-out areas are called swales. The purpose of a swale is to drain the water away to a suitable location before it reaches the house. It's similar to the design of highways. The paved road is set at a higher level than the side areas with the grass and trees. This will help drain the rainwater away from the roadway.

As I said earlier in the book, recommend that the client check with the local building department to figure out if the house is located in a designated flood hazard zone. If it is, then flood hazard insurance will be needed.

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