Eight-inch thick concrete foundation walls have about the same insulation value as dual pane windows. Imagine the heat loss of wall to wall windows around and under your floors. Since heat flows from hot to cold, the masonry walls, which are exposed to outside temperature and wind, are constantly robbing heat from the warmer floors above and from your heat delivery system. Most houses have part of their heat delivery system, hot water pipes or air ducts, running through the crawl space. Forced air at 130 degrees or hot water at 160 degrees, even when in insulated ducts or pipes, looses a lot of heat to the cold crawl space air and radiates the heat to the even colder walls before it gets to the rooms it is supposed to heat.

We use foil-coated batt insulation to keep crawl space walls from sucking valuable heat from warm floors, hot water pipes and heat ducts.

The Fix
We can insulate your cold perimeter walls with a 4-foot wide, 2-inch thick fiberglass fire-rated foil-faced blanket, rolled out horizontally to minimize seams (seams in insulation are like open zippers in down parkas.) and notched to fit tight around floor joists. The reflective surface bounces heat away from the cold masonry walls and back up to your floor, helping to raise your floor surface temperature and the overall temperature in the crawl space. Bare feet and children playing will appreciate that!

Moisture
The second culprit is the bare earth below. Soil, and even to an extent, cements floors, is contiguous and wicks away moisture (capillary action) from moist to dry areas. The relative warmth of crawl spaces dries the topsoil by evaporation, which in turn wicks up additional moisture from the melting snow in your yard and in the soil on down to the water table below.

Evaporation is a cooling process and the energy used to evaporate the moisture is your heat! Besides cooling off the home above, as well as the heat distributed, it can lead to aggravating condensation on windows and in some cases, on walls leading to mold growth.

The Fix, Part II
We spread a clear, heavy-duty plastic vapor barrier over the bare earth that prevents the heat-robbing evaporation and stabilizes the moisture content to be equal to the adjacent soils. The sun outside your foundation, then, becomes the evaporator, pulling moisture away from your home, not to it! Use free solar energy, instead of the heat you pay for, to evaporate excess moisture from the soil below and around your home.