I have a vented crawl space, the floors are not insulated. In the winter the floors are very cold. Should the vents be covered?

Asked by Thom
Wallkill, NY

foundation is block, crawl is dirt floor, 6 to 18 in clearance, floors of house are half tile, half carpet, location is New York


Answered by Michael Hein

North Lima, OH

The Green Building Pros, Ltd

January 29, 2014

You can fix this problem two ways. One is get rid of the vents and encapsulate the crawl space to include it in the "conditioned space". This means air sealing and insulation, vapor barrier on floor, insulating the walls, and insulating the rim joist OR You could insulate the floor joists to seal OUT the crawlspace area, keep it out of the conditioned space, and keeping it literally connected to the outside. Insulating the joists may entail a foam board on the underside of joists, and then dense packing cellulose in cavities. IF you have ductwork and/or plumbing in crawl space, I highly recommend the first answer, that way you can keep them "inside" the conditioned area.

Tagged In: crawl space, building envelope

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