Moisture Barrier Garage Ceiling

Attached garage not finished except ceiling and walls adjacent to house.

Moisture barrier garage ceiling.

I would like to insulate and drywall the walls. It s also incorrect in a way. I will not be heating in winter live in wisconsin so summers can be hot and winters. To know if you need a vapor retarder ask yourself a few basic questions.

If you re using old uninsulated doors pick up a retrofit kit that add insulating panels. Vapor barrier in garage ceiling. All attics vented or unvented should have an air barrier a properly detailed airtight drywall ceiling for example regardless of climate. 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.

Water vapor can pass through building materials in several ways including direct transmission and by heat transfer but studies suggest that fully 98 percent of the moisture transfer through walls occurs through air gaps including cracks around electrical fixtures and outlets and gaps along baseboards. Doing this will only trap water vapor inside your garage. Proper installation of a wall vapor barrier or using insulation products with a built in vapor barrier will reduce garage condensation a vapor barrier can also be used to cover the floor but avoid using it on garage ceilings. The ceiling is not insulated and does not have vapor barrier installed.

Omitting a ceiling vapor barrier by arguing that you have to let the moisture escape or because the house has to breathe out the top is actually correct in a way. Use a vapor barrier. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter. And the ceiling acts as a enough of a vapor retarder.

Wall vapor barriers on the other hand can prevent. First of all a garage is not a signicant source of vapor as it is not occupied that much and you don t cook or bath in in it. Install as directed typically cutting to fit and using a staple gun to attach the vapor barrier to the studs. Thus installing vapor barriers on wall surfaces must.

So you don t need a vapor barrier in the garage ceiling. If you re adding new garage doors be sure to install insulated options. Ceiling vapor barriers are a bad idea because they keep water vapor trapped inside the garage according to home improvement expert tim carter.