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An interior, insulated, friction fit door is installed behind the existing crawl space door.
Spray Foam insulation is installed on the crawl space walls and the vents, rim & band, and sill plate are sealed and insulated.
This Dewitt, VA crawl space is encapsulated with a 20-mil CleanSpace vapor barrier, closed-cell spray foam, a SaniDry Sedona Dehumidifier, R-11 along the perimeter of the crawl space, and an Everlast Crawl Space door.
The standard vapor barrier that is installed in the crawl space during construction is a flimsy 6-mil liner that is easily torn apart by any service persons, rodents, and pests who crawl on top of it. This ineffective vapor barrier does not get properly sealed around the piers or foundation walls. Moisture from the earth floor rises into the crawl space through these gaps, adding to the relative humidity if the temperature rises.
CleanSpace is a 20-mil thick vapor barrier that completely seals off the home from the earth’s moisture. It is wrapped around the piers and sealed to the foundation walls using a 4” wide vinyl tape. Moisture rising from the ground is not able to penetrate the CleanSpace liner, adding to the total control of relative humidity in the crawl space.
The open vents allow moisture and outside air into the crawl space. This makes it extremely difficult to control the overall relative humidity underneath a home. The dry winter air entering the vents will cause the floors above to feel cold and drafts, as well as raising the energy costs to keep the house comfortable. And in the summer, the wet, hot air will carry moisture into the crawl space, raising the relative humidity and allowing mold and mildew to thrive.
The foundation walls of this crawl space have been sprayed over, using a closed-cell spray foam that provides not only insulation but blockage from outside air moisture, while the open vents were sealed with foam board and covered in the same closed-cell spray foam. When closed-cell spray is applied at 1.5” thickness, it acts as an air barrier and vapor retarder. Sealing off the outside air and moisture provides the homeowner with more control over the relative humidity in the crawl space.