Because concrete is porous, moist air can enter the house through the foundation walls and floor. This is one of the main reasons for damp basements. The best way to deal with this is to make sure that there is good drainage around your house. It is important to maintain the following:
- The backfill around your house should slope down away from the house. Consult with a landscaper if there aer issues with the grading around your house.
- Gutters should be periodically checked and cleaned of leaves and other debris that can cause rain to overflow.
- Downspouts and extensions should direct runoff away from the house foundation.
- If there is a sump pump in your basement, make sure that it is operating properly and pumps the runoff away from the house.
Using a dehumidifier will also help to keep your basement dry. During the summer, warm humid outside air can condense on the cool foundation walls and floor. A dehumidifier can help to remedy this problem.
RELATED LINKS AND FILES
Home Moisture Guide.pdf
(Acrobat - 487K)
This guide describes the symptoms of moisture problems, lists common indoor and outdoor causes, and discusses ventilation as a preventative and corrective measure.Basement Guide.pdf
(Acrobat - 462K)
This guide includes recommendations for both new and retrofit foundation wall insulation. Completely revised as of 6/02. 
