Does Attic Insulation Need A Vapor Barrier

You do not need a vapor barrier.

Does attic insulation need a vapor barrier.

If you read the brief it points out the major concern with moisture in insulation is air leakage. 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. Not every wall does. Attic insulation should always be installed with the paper backing facing toward the living space the ceiling in this case.

Several layers of paint on the ceiling would qualify as a vapor barrier. A plastic vapor barrier is best installed in a vented attic within climates with over 8 000 heating degree days. The following are a few simple steps to help you undertake the task properly so your vapor barrier retains heat without damaging the insulation. Since you already have insulation if there was a moisture problem you probably would have noticed signs of it already.

Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter. 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. After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one.

The insulation fiberglass or cellulose is then placed on top of the drywall with no vapor barrier above or below.