Vapor Barrier

[Eric Smith]

Have a buddy who is building a home in country and very rustic. He is using old barn wood AMD used corrugatetal on interior walls. He is asking me if a vapor barrier is required. He has installed unfaced 6 inch insulation and has it nicely house wrapped. At first I thought yes because of the air and vapor that can pass through the openings in the rustic materials but then I started to think that it shouldn't get trapped in the wall cavity either. Thoughts?

[Dom D'Agostino]

Lots of info about vapor barriers, and vapor transmission through buildings.

Q&A: Is a Vapor Barrier Necessary? - JLC Online (http://www.jlconline.com/building-envelope/q-a--is-a-vapor-barrier-necessary-.aspx)

BSD-106: Understanding Vapor Barriers ? Building Science Information (http://www.buildingscience.com/documents/digests/bsd-106-understanding-vapor-barriers)

[John Kogel]

In my climate, always always a vapour barrier behind the interior wallboard.
The housewrap is designed to breathe just enogh to let any stray moisture out.