Does a Wall in Manitoba Need a Vapour Barrier?
Yes. Under the National Building Code of Canada, a vapour barrier is required in insulated wall assemblies throughout Manitoba, and the requirement…
Does a Wall in Maine Need a Vapor Barrier?
Yes. Maine’s counties fall inside IECC Climate Zones 6A and 7, and the 2021 International Residential Code requires an interior vapor retarder on frame…
Does a Wall in Louisiana Need a Vapor Barrier?
No. Under the 2021 International Residential Code, Section R702.7, Louisiana falls entirely within the climate zones the code exempts from the interior…
Does a Wall in Kentucky Need a Vapor Barrier?
Kentucky sits entirely inside IECC climate zone 4A, and that single fact settles the question: the 2021 International Residential Code’s exception for…
Does a Wall in Kansas Need a Vapor Barrier?
A wall in Kansas needs an interior vapor retarder under the 2021 International Residential Code, because none of the state’s counties fall into the…
Does a Wall in Iowa Need a Vapor Barrier?
Yes. Every one of Iowa’s 99 counties sits in a cold climate zone under the 2021 International Residential Code, so the exception that removes the vapor…
Does a Wall in Indiana Need a Vapor Barrier?
Yes, in most of Indiana a wall needs an interior vapor retarder under the 2021 International Residential Code.
Does a Wall in Illinois Need a Vapor Barrier?
Illinois frame walls need an interior vapor retarder under the 2021 International Residential Code, and that answer holds whether a house sits in the…
Does a Wall in Idaho Need a Vapor Barrier?
Yes, most of Idaho falls under building code climate zones that require an interior vapor retarder on framed walls.
Does a Wall in Hawaii Need a Vapor Barrier?
Hawaii sits entirely in IECC Climate Zone 1A, and under the 2021 International Residential Code, a vapor retarder is not required in Climate Zones 1, 2…