We will launch our tour together in the basement or crawl space seeking moisture, figuring out its source, and providing solutions to the problem. The most common dampness in below grade foundations originates from outside the building. Moisture intrusion is caused by inadequate control of surface and ground waters. The results can be discolored walls, seepage on the floor around the perimeter of the foundation, or a completely flooded basement.
So what causes these conditions?
The most common cause of basement moisture is improper landscaping. Simply put the earth grading is sloped towards the foundation. This is called negative slope. The first step in managing surface water is to make sure the earth slopes away, positive slope, from the foundation on all sides of the building. Even the smallest depressions or settlement of soil can trap water allowing it to dampen the walls and stain the foundation.
Although type of soil can have an impact on whether surface water will enter the building, there are 3 common grading defects that should always be corrected. They are:
So we see that landscaping is always a problem, but is that the only thing on the outside of the home that causes moisture intrusion? Check back soon for part 3 in our home moisture problem resolution series!
Doug & Julie Hastings
Your House Whisperers
Residential & Commercial Home Inspectors