Vapor Barrier Attic Floor

Because it s nearly impossible to seal penetrations in the ceiling the reality is water vapor will get into the attic.

Vapor barrier attic floor.

This acts as a barrier to keep heated moist air from rising up into the attic during cold weather. Most forms of attic insulation benefit from the addition of a vapor barrier to protect them from the harmful effects of moisture which can reduce their effectiveness over time. A vapor barrier against the concrete surface is generally recommended before wood framing or flooring materials are installed. Attic insulation should always be installed with the paper backing facing toward the living space the ceiling in this case.

The following are a few simple steps to help you undertake the task properly so your vapor barrier retains heat without damaging the insulation. Below grade walls and floor slabs transmit ground moisture through concrete walls or slabs. Even though we apply vapor barriers to exterior insulated walls in cold climates it s no longer recommended for ceilings floor of the attic. Attic vapor barrier detail for cold climates.

If your climate does not meet these conditions a vapor retarder like latex ceiling paint will work well for your house if you are in all other climates except the hot dry and hot humid. Crawl spaces benefit from a polyethylene moisture barrier placed directly over the exposed earth. A plastic vapor barrier is best installed in a vented attic within climates with over 8 000 heating degree days.