Do I Need A Vapor Barrier For Attic Insulation

Then cover the foam with drywall as required for fire safety.

Do i need a vapor barrier for attic insulation.

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. After the insulation is in place you will want to add a vapor retarder sometimes called a vapor barrier if you need one. The heat being lost from the house below warmed up the attic so that moisture was lost through the vents as vapor. Plastic vapor barriers should only be installed in vented attics in climates with more than 8 000 heating degree days.

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. Because it s nearly impossible to seal penetrations in the ceiling the reality is water vapor will get into the attic. Attic vapor barrier detail for cold climates. Whether or not you need a vapor retarder hinges on three main factors your climate your home and the location of the wall you re insulating.

This acts as a barrier to keep heated moist air from rising up into the attic during cold weather. Our insulation vapor barrier can also reduce condensation mold and degradation by controlling water vapor migration. With spray foam unlike with loose fill or batts you must cover the soffit vents they aren t needed to keep the roof cool. Foam blocks airflow needs no vapor barrier and has a higher r value per inch than loose fill or batts so you ll get more protection with less depth.

Not every wall does. Crawl space ninja insulation vapor barrier is a blanket insulation vapor barrier designed to provide a thermal break and moisture barrier in crawl spaces. 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. Insulation vapor barrier with radiant barrier.

Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers. Even though we apply vapor barriers to exterior insulated walls in cold climates it s no longer recommended for ceilings floor of the attic.