Healthy Indoors
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was constantly evaporating water into the crawl space air.
The good news is that most new homes do get vapor
barriers put down on the ground, eliminating a lot of the
moisture that comes from the soil.
3. Foundation walls
Moisture can also come from the ground outside the house
by migrating through the foundation walls. Vented crawl
spaces rarely get any kind of damp-proofing or perimeter
drains on the exterior. As a result, wet soil outside the crawl
space can come right through, as you see below.
The crawl space in the photo at right had a lot of this
moisture. The backyard sloped down toward the house,
putting a lot of hydrostatic pressure against the bare con-
crete block wall. You can see how well that worked. The
whole crawl space had an inch or two of standing water.
