Insulating a metal barn
I have read a lot about condensation problems when insulating metal barns, as well as your blogs on bubble wrap scams and subsequent commentary.
I am considering installing a rigid moisture resistant insulation board (polystyrene) against the wood girts of the metal barn, leaving an approx 2″ air space between the edge of insulation and the metal siding. Despite all the negative comments about foil faced bubble wrap, I am considering installing possibly a single bubble wrap product with foil on both sides flush with the 8″ wood framing timbers, (with supplemental furring strips), to create both a moisture barrier, reflective foil to keep the heat inside the barn, and importantly, to create a second air pocket of approx 4-5″ between the bubble wrap product and the rigid board insulation. Since I can purchase the bubble wrap for about $0.20/sqft. (about the same cost of just a radiant foil w/o any R value and perhaps less strength as a siding material), I see the primary benefit of the bubble wrap with foil as a radiant and moisture barrier….not its insulation benefit. I estimate that this assembly will produce an R value of approx 19-20 (7 for each air pocket, 1 for the bubble wrap and 5 for the 1″ rigid insulation board.
Your thoughts/comments/suggestions will be greatly appreciated.
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