ᐅ Is a vapor barrier always required with exterior (above-rafter) insulation?
Created on: 11 May 2016 06:16
S
S.BrandtHello,
Our roofing company told us that instead of a vapor barrier below the exterior insulation on the rafters, they want to install a Delta-Sd Flexx renovation vapor retarder. They said this is better.
This concerns a new build where we plan to leave the roof structure visible from the inside. The assembly is planned as follows:
1.) Rafters
2.) 19mm (3/4 inch) visible boarding (spruce wood)
3.) Delta-Sd Flexx renovation vapor retarder (?????)
4.) Bauder PUR exterior insulation on rafters, 180mm (7 inches), WLG026, coated with mineral fleece
5, 6, 7.) Battens / Roofing
They said that if I insisted, they would install a PE foil instead of the Delta vapor retarder.
Has anyone had experience with what would be the most sensible solution here? I can’t really question the expert, but it’s okay to have doubts :-)
Thank you!
Our roofing company told us that instead of a vapor barrier below the exterior insulation on the rafters, they want to install a Delta-Sd Flexx renovation vapor retarder. They said this is better.
This concerns a new build where we plan to leave the roof structure visible from the inside. The assembly is planned as follows:
1.) Rafters
2.) 19mm (3/4 inch) visible boarding (spruce wood)
3.) Delta-Sd Flexx renovation vapor retarder (?????)
4.) Bauder PUR exterior insulation on rafters, 180mm (7 inches), WLG026, coated with mineral fleece
5, 6, 7.) Battens / Roofing
They said that if I insisted, they would install a PE foil instead of the Delta vapor retarder.
Has anyone had experience with what would be the most sensible solution here? I can’t really question the expert, but it’s okay to have doubts :-)
Thank you!