Side Note: Crawl Space

Wood + Water = BAD NEWS

Exposed earth contributes a lot of water vapor into the crawl space air.  The earth is damp and as that damp soil dries into the house.  In climates where there are dirt crawl spaces, you can never dry the earth, and this invisible stream of water vapor from the exposed earth in a crawl spaces continues forever.

There are several ways water gets into a house.  Groundwater seeps, leaks or could even rush into many crawl spaces.  It can enter under the footing, between the footing and the walls, right through block walls, and through cracks in poured walls.  After it seeps in, it just lays there in puddles, slowly evaporating upward into the house.

Some of the common symptoms of a crawl space moisture problem are:

  • Mold or moisture damage in the crawl space or living area
  • Musty odors in the living area
  • Condensation (“sweating”) on air conditioning duct work or equipment
  • Condensation on insulation, water pipes or truss plates in the crawl space
  • Buckled hardwood floors
  • High humidity in the living area
  • Insect infestations
  • Rot in wooden framing members

These symptoms are most often noticed in the humid spring and summer seasons but can occur at any time of the year. Often, the heating and air conditioning contractor is the first person the residents call to deal with the problem. Typically though, the problem is not due to a failure of the air conditioning system; it results from poor moisture control in the crawl space.

Keep up with our Side Note Series for more information on crawl spaces and how to maintain them.

 

Excerpts from Dry Basement Science – What to Have Done and Why by Lawrence Janesky