Some debate still occurs over how necessary vapor barriers are but a consensus is growing closer.
Vapor barrier roof rafters.
Its closed cell structure stops water vapor and the foil covered face acts as a radiant barrier.
Vapor barrier on under side of floor joists over a crawl space oct 26 2011 alex in seattle said.
A vapor retarder is a material used to prevent water vapor from diffusing into the wall ceiling or floor during the cold winter.
That is create a vent channel above the insulation with low and high vents.
Resolution of the vapor barrier debate.
I thinking walls 1 closed cell then blow in followed by vapor barrier and steel panel.
From what i ve read online it seems wise to install a vapor barrier over the plywood to prevent condensation from getting absorbed into the plywood from the steel roof.
Plan is to after foam put barrier and steel panel up and then.
Attic vapor barrier detail for cold climates 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.
No wrap on walls.
But it seems the.
Hopefully you have installed a vapor barrier between the roof purlins and the roof steel.
Most authorities now agree that vapor barriers are important under certain conditions but not necessarily as a whole house solution for every home.
4 times the cost of fiberglass batts.
Not recommended for exterior below grade applications.
Not flammable but it must be protected with wallboard.
That reduction of air and moisture infiltration can then help improve roof longevity.
You could insulate the roof the traditional way.
A roof design that includes an adhered roof membrane with multiple layers of insulation with board joints offset and staggered over a vapor retarder air barrier helps lower the risk that air and the moisture it carries will infiltrate the roof system.
White bubble between roof and rafters.
The previous owner has 1 foam insulation with a a plastic vapor barrier only on the rafters of the roof about4 from the slate roof but not on the walls of the attic.
To know if you need a vapor retarder ask yourself a few basic questions.
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.
Whether or not you use vapor retarder you want an air tight air barrier such as well sealed drywall to keep out moisture from the house.
I have a 1961 single story home with a cement floor crawl space.
There are certainly other options.
The insulation fiberglass or cellulose is then placed on top of the drywall with no vapor barrier above or below.
In circumstances where conditions inside a home or office are much different than outdoor conditions water.
