Attic Insulation Moisture Barrier

When adding additional insulation to an attic that is already insulated never use insulation with a vapor barrier.

Attic insulation moisture barrier.

If you do there is a chance that moisture that has slipped by the first vapor barrier will become trapped by the second vapor barrier decreasing the value of your insulation. Whether you use it in a crawl space radiant floor attic or walls you ll find it easy to handle and install. 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 the following are a few simple steps to help you undertake the task properly so your vapor barrier retains heat without damaging the insulation. Double reflective insulation roll with staple tab edge for a versatile insulation product select for a versatile insulation product select reflectix insulation to help save energy costs throughout the home.

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. If installed on top of attic floor insulation the foil will be susceptible to dust accumulation and may trap moisture in fiber insulation so it is strongly recommended that you not apply radiant barriers directly on top of the attic floor insulation. Not every wall does. If you live in a cold climate place the vapor barrier between the interior of your home and the insulation.

In any case the vapor barrier must point to the warm side. Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers. 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. The insulation fiberglass or cellulose is then placed on top of the drywall with no vapor barrier above or below.

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. Some regions don t require a vapor barrier. Whether your vapor barrier is a facing or a film it must be placed on the warm in winter side of the wall. Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets.

A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter.