Siding/insulation/WRB/drainage etc. -- shorter question
I have a question with somewhat less detail than my last volley :)
I am building a new house 100 yards from the ocean - elevated approximately 10' off grade. fiber cement siding
Connecticut shore - 4+ or 5- mix of humid/warm and first cold zone = maybe 40 rain days... near water - driving rain elevated (somewhat protected by large eaves and gable end over hangs). right on the edge of both zones.
Specs - as they stand right now. Still a few weeks out (can easily change up to application for building permit). From inside out:
3/4" southern yellow pine bead-board (essentially flooring installed on the wall). Stained and poly coated both sides prior to installation. TG 6" wide panels. nailed in channel to substrate next layer.
4" horizontal bars (cut full 8' length) of plywood fastened to studs (for support to nail bead-board into. This is instead of full ply wood coverage for nail base. will air gap have any effect ? too shallow to use for wiring chase... should we just use full plywood coverage and tape seams inside too?
(insert vapor barrier here?) with external foam, we'll still need to dry to the inside? Looking at Intello Plus, from 475 (see: http://www.foursevenfive.com) plus, this will surely help with continued efforts to maintain tightly sealed home.
2x6, 24 oc standard dimension lumber framing with Roxul 5.5 inch batts = R23.
Fiber coated gyp sheathing 1/2 or 5/8 (structural engineer still working on sheer loads, etc)
WRB layer (which brand and why?)
Hunter xci ply bonded to polyiso foam = 2" foam, 3/4 plywood installed with 7-8" screws into stud One layer - taped at seams. R12 is good for 2/3 in, 1/3 out insulation. Can go to 2 1/2 inches to make R value outside 15 or 16.... ?
WRB layer again - same - which and why.
Trimline plastic 3/8" furring strips (for drainage plane) tacked on. vertical.
Fiber cement installed over furring directly into 3/4 plywood.
short story long...
a. what WRB and do you agree it is needed in two places?
b. install vapor barrier interior side of insulation?
c. agreement on the amount of insulation as proper ratio of in/out ?
any other thoughts which I missed or screwed up?
Posted Tue, 09/10/2013 - 14:35
Edited Tue, 09/10/2013 - 19:00
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