Attic Insulation Vapor Barrier Up Or Down

Not every wall does.

Attic insulation vapor barrier up or down. Affix rigid foam insulation to the attic side of the hatch or door. This acts as a barrier to keep heated moist air from rising up into the attic during cold weather. Attic vapor barrier detail for cold climates the best approach for a vented attic in a cold climate is installing a layer of drywall with a good coat of latex paint the paint creates a semi permeable vapor barrier. My biggest concern right now is the vapor barrier.

Attic hatch or door. Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets. You have made the bold decision to insulate your attic. Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers.

In any case the vapor barrier must point to the warm side. The heat being lost from the house below warmed up the attic so that moisture was lost through the vents as vapor. The insulation fiberglass or cellulose is then placed on top of the drywall with no vapor barrier above or below. As of right now there is about 7 of blown in insulation in the attic.

What if you find asbestos in your attic. Now with attic insulation heat is no longer lost from the living space such that moisture may remain trapped in the attic vapor barriers were therefore necessary to reduce moisture flow into the attic. Pull down stair or ladder. Add weatherstripping around the perimeter and a sweep to the door of a walk up attic.

If the batts are your only layer meaning the attic joists are currently uninsulated you should install them with the vapor barrier down facing your living area below. In this case use r 38 insulation as recommended above by energystar. If you install fiberglass batt insulation with a kraft paper vapor retarder in a home which way do you face the vapor retarder. For many building science questions the answer is it depends for this one the answer is clear.

This barrier is meant to keep moisture from getting to the insulation in the walls and ceilings and it is required by building codes when insulating most houses. Attic insulation should always be installed with the paper backing facing toward the living space the ceiling in this case. To the inside of the home or the outside of the home. Yes you should put unfaced insulation either rolls or batts on top of existing insulation so that you only have on vapor barrier facing the heated house.

After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter. I do not see a vapor barrier underneath the current insulation.