Building a house in Zone 6
user-6724719
| Posted in GBA Pro Help on
Building a house in zone 6. Framing nearly complete. Too cold to roof now with asphalt shingles, but rain protection needed. Roofer asked builder if he should extend the “ice shield” which I understand is vapor impermeable, over the whole roof, or cover with ?
Issue relates to the potential trapping of moisture in the sheathing if two impermeable membranes are used.
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Replies
I would use synthetic tar paper with cap nails of some type. It would be more economical for starters.
As Scott said: Many synthetic underpayments secured by cap nails are rated for six months without a finished roof. That said, asphalt shingles don't allow any significant drying to the outside anyway, so IWS would do no harm.
Frank,
Scott and Malcolm have given the correct answer. The usual solution is to install synthetic roofing underlayment. This will cost less than a peel-and-stick product like Ice & Water Shield. Moreover, future repairs (access to the roof sheathing) will be simpler if you use synthetic roofing underlayment.
-- Martin Holladay