Polyethylene Vapor Barrier Attic

Even though we apply vapor barriers to exterior insulated walls in cold climates it s no longer recommended for ceilings floor of the attic.

Polyethylene vapor barrier attic.

4 8 out of 5 stars 14. Plastic vapor barrier in attic prior to blown insulation i am going to blow insulation into my attic and noticed one video where the people put down plastic over the floor studs as a vapor barrier prior to blowing the insulation. Without a vapor barrier in place condensation inside the walls could ruin the. Vapor barriers are sheets of plastic or other material placed on one side of insulation sheets.

Crawl spaces benefit from a polyethylene moisture barrier placed directly over the exposed earth. This same process occurs inside the walls of your home. If you re in maine and never use an air conditioner a vapor barrier on the inner surface may be ok. You could be creating the kind of problems i described in scenario 1 above.

Adding a second vapor barrier could cause condensation to become trapped in the insulation between the two vapor barriers. A plastic vapor barrier is best installed in a vented attic within climates with over 8 000 heating degree days. 1 16 of 726 results for polyethylene vapor barrier 1000 sqft 4x250 solid white vapor barrier attic foil white radiant barrier reflective solid insulation 4x250ft non perforated woven polyethylene scrim heavy duty. If you re in a cold climate however and do use air conditioning you need to be careful with interior vapor barriers like polyethylene.

Attic insulation should always be installed with the paper backing facing toward the living space the ceiling in this case. A vapor barrier against the concrete surface is generally recommended before wood framing or flooring materials are installed. Tips for installing vapor barriers. Plastic vapor barriers should only be installed in vented attics in climates with more than 8 000 heating degree days.

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. In any case the vapor barrier must point to the warm side. Because it s nearly impossible to seal penetrations in the ceiling the reality is water vapor will get into the attic. 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.

Condensation occurs whenever warm air meets cold air.