Vapour barrier confusion
Hello from Canada,
I have been searching for a few days now for an answer about the use of a vapour barrier in conjunction with 1″ rigid foam and Tyvek on the exterior of a wooden frame house with 2″x6″‘walls insulated with fibreglass batt. I am more confused than when I started now!
We had wanted to use 2″ foam but the contractor refused so now we have used 1″ rigid foam with Tyvek and wooden clapboard siding. So that’s finished and now we are dry-walling and I was wondering if we needed a polyethylene vapour barrier on the inside.
It seems that first of all, the foam is not thick enough (I would be in probably between Zone 6 and 7 according to the charts, or ‘Very Cold’). So after all the reading I’ve been doing I fear that mistakes have been made that cannot be fixed easily (not without completely redoing the foam and clapboard) so I guess that leaves me with two questions:
1) is there anything I can do to fix this?
2) do I need an interior vapour barrier and, if so, what kind is best?
Thank you kindly for your help and my apologize s for the long-winded questions.
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