Climate zone 4 double stud wall vapor barrier
I am in the process of designing and then building a timber frame cottage for my property located outside Victoria, BC (climate zone 4 or 4c depending on which map you check). So mild and damp, and given that I am in the woods, damper than average for the area.
I am thinking that a double studded 2×4 wall with staggered studs, using rockwool comfort bats(3 layers), will get me in the R38 range (exterior is 3/4 board and batten fir on vertical strapping with horizontal purlins).
The head scratcher is where to put the vapor barrier. If possible, I would like to put it on the inside of the inner stud/insulation layer, and use tar paper/felt as the moisture barrier on the external plywood sheeting.
I feel that this would keep the condensation point away from the vapor barrier, and allow drying in both directions.
Any feedback to say I’m on track or way off base is appreciated.
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