Vapor Barrier Tongue And Groove Ceiling

It s also incorrect in a way.

Vapor barrier tongue and groove ceiling.

I am attaching the planks directly to the bottom of trusses. My thought is to remove the batts and install 1 foil faced foam board foil towards the heated rooms then seal any gaps between the foam board and ceiling rafters. For example see how to build an insulated cathedral ceiling. If you pay attention to airtightness when you install your air barrier you don t have to worry very much about vapor diffusion.

The biggest air barrier blunder is to install tongue and groove boards as your finish ceiling without first installing taped. To know if you need a vapor retarder ask yourself a few basic questions. I am considering putting up poly or tyvek. A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter.

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. Gba has long advised people installing a tongue and groove board ceiling to first install an air barrier of gypsum drywall. The article includes this advice. I am adding a tongue and groove cedar plank ceiling to a heated room in my pole barn.

Don t forget to use airtight electrical boxes and to seal all of the air leaks at all penetrations. 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. That leads me to believe heated air may be escaping the rooms through the gaps. I am concerned with air dust dirt leakage between the planks.

Should i have a vapor barrier between the planks and the blown in insulation.