Is my re-roofing strategy adequate?
I just visited the supplier that I’m planning to get my foam board and metal roofing from. I was struggling to decide my strategy before, but now I’m really confused.
I an reroofing a 118 year old bungalow in central Indiana, zone 5. My plan is to tear off shingles to the wood board sheathing, repair, wrap in air barrier/membrane, 2 layers of 2″ foam board (probably foil faced polyiso) seams taped and staggered, then horizontal purlins attached with 7″(+) screws. I’m installing exposed fastener metal roofing on top.
After talking to the supplier, he’s trying to lead me in a totally different direction. I had a hard time getting him to understand the whole unvented, “hot roof” assembly. He said I should- “Leave the single layer of existing shingles, lay horizontal purlins over them, then cover everything in that foil bubble wrap stuff. Then metal roof on top. In the rafter bays, cut 2.5” polyiso to fit. He says “I’ve been working in this industry for 30 years, you cant believe everything you read on the internet. Ha.
Anyway… I’ll probably stick with something similar to my original idea. The awesome thing is, this supplier has salvaged foam board that’s basically in near mint condition for 4x8x2.5″ @ $10 ea and other similar prices.
He said I should definitely use a vented closure, letting air between the metal and the purlins. Is vented closure a good or bad idea?
Thanks if you actually read all of that rambling… I have to do the work 100% my self, I’m on a tight budget, and I’m kind of freaking out
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