Concrete Foundation Walls - Water Leakage
Problem: Water leakage through foundations - 1.
Cause: Inadequate site drainage.
Solutions: Ensure that rainwater is diverted away from the foundation.
- While a 2 percent slope away from foundation walls is commonly specified, a 10% slope away from the wall for the first 6 1/2 feet which is 8 inches, is recommended. This increase will ensure positive slope away from the building after the ground has settled around the foundation as shown in figure 21.
Figure 21 - Proper Site Drainage
- Locate downspouts around the perimeter of the building to ensure that rainwater is directed away from the building. Provide splash blocks to promote positive flows and to prevent erosion.
- On a sloping site, place the building at an angle to the slope to prevent the house form acting as a dam to natural run-off, or grade from the center of the house to the corners to direct water away from the building as shown in Figure 22a and 22b. Provide swales to promote drainage.
Figure 22a - Sloping Sites - Angle House
