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barndominium – GreenBuildingAdvisor
I took down an 150 year old barn and rebuilding to a livable space. Im not sure what to do about vapor barrier. Since beams and old siding are up I need to add continuous insulation to outside.
Starting from inside, my wall will be
-1x old barn material
– vapor barrier?
– 3″ ISO Board
– 2″ XPS taped all seams-
-1x furring strips( vent on top and bottom)
– Hardi board siding.
Since old siding which is now finished interior is not tight I will see ISO board. ISO board is not foil faced it is roofing ISO which has a paper or felt like finish.
Is Iso board OK or do I need a vapor barrier before ISO
If vapor barrier what type?
Thanks
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Replies
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Expert Member DCcontrarian | | #1
If you don’t want to see the poly through the cracks, you can get black rosin paper.
I don’t think you need a vapor barrier. Do tape the seams if you can.
Sounds like a fun project.