Options for air and water barrier and local qualified builder for this roof system
Well here’s my dilemma, Houston TX, 50s rancher, 3/12 pitch, plank deck, 2.5’ overhangs enclosed soffits.
No working room in attic, mostly filled up with ridged AC ducts, lots of alarm wireing, max height at ridge 30″ and very limited access to eve area, <2” rock wool batt insulation in bad shape.
So will change to “conditioned” attic, and go with 5” ISO above deck, vent channel above foam, OSB or PLY top deck, underlayment and OC cool shingles.
My only options for the WRB / AIR Barrier is on primary deck or middle layer of foam unless I site build the vent channel
The Dilemma: wrb / vb locations ??
Option 1: peal and stick on primary deck. Least labor $$, quickest dry in. Problem is I can’t find anyone who can honestly tell me if I will get an odor from the asphalt adhesive into the living area through the ship lap deck.
Option 2: peal and stick over bottom 3” layer of foam with Thermacal 1 with 2” iso and 1.5” vent channel over that, a lot more labor $$$ but would eliminate odor from peal and stick. screws night not seal as well due to shredding of the sealent.
Option 3: site build vent channel and put peal and stick above both layers of foam under screeds, this would give the best screw sealing ability from the Peal & Stick. A lot trickier to build, ( anybody know a builder in Houston with this kind of experience ) Labor $$$$
Top deck will be traditional roofing system, OSB or PLY, I&W, solar reflective OC Cool shingles
Any thoughts, suggestions,
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