Attic Insulation Vapour Barrier

In hot dry climates your attic can be vented though like in hot humid climates you should not install any vapor retarder or barrier.

Attic insulation vapour barrier.

The insulation fiberglass or cellulose is then placed on top of the drywall with no vapor barrier above or below. A vapor barrier basically helps to prevent moisture from entering your home through the ceiling floor or the walls. This acts as a barrier to keep heated moist air from rising up into the attic during cold weather. Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers.

Attic insulation should always be installed with the paper backing facing toward the living space the ceiling in this case. It is a known fact that moisture in the air can trigger certain disorders and aggravate particular medical conditions such as hay fever asthma etc. 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. In any case the vapor barrier must point to the warm side.

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. 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.