Attic Insulation Vapor Barrier Or Not

This acts as a barrier to keep heated moist air from rising up into the attic during cold weather.

Attic insulation vapor barrier or not.

Some regions don t require a vapor barrier. Even if it asks you to. Not be trapped inside. Since some leakage of moisture into the insulation in inevitable murphy s law you want it to be able to freely escape from the insulation into the attic.

Whether using loose fill or batts put the vapor barrier closest to the warm side of your installation where hot moist air would get in facing the house s interior in cold climates beneath floor insulation and the attic s interior in hot climates on top of floor insulation. Plastic vapor barriers should only be installed in vented attics in climates with more than 8 000 heating degree days. Never compress or fluff your insulation. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter.

You can forego the plastic and use a vapor retarder kraft faced insulation or latex ceiling paint in all other climates except hot humid or hot dry climates. Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers. Before the introduction of attic insulation attics in cold climates were poorly insulated and plastic ceiling vapor barriers were omitted. 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.

After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one. Fiberglass insulation must stay dry to be effective. A damp attic can also be the cause of discomfort and lower air quality in the living space. Not every wall does.

Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets. Attic insulation vapor barrier or not. When considering the health of your attic the issue of moisture is exceedingly important. You want to keep your attic as dry as possible to protect the area from mold and mildew as well as rot.