Can Housewrap ‘melt’ under steel siding?
user-7015584
| Posted in GBA Pro Help on
I am installing metal siding on a new construction Home and planned on installing Hydrogap by Benjamin Obdyke underneath. The siding contractor has expressed concern that the paper or the dimples on it may melt.
Has anyone ever experienced housewrap ‘melting’ from the suns heat.
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Sorry, as a clarification I live in climate zone 5
User 701etc.,
Can you tell us your name?
According to the Hydrogap web site, HydroGap is compatible with metal siding. But if you have any doubts, call up Benjamin Obdyke's technical help line (800-346-7655).
Hi Martin,
Appreciate the feedback. I didn't find any commentary about paper 'melting' online. My installer wants me to use Titanium PSU30 instead of the Hydrogap.
Thanks
Peter
Peter,
You need to get another installer. Your installer is ignorant.
The synthetic roofing underlayment suggested by the installer (a) is a roofing product that is not designed for use on walls -- meaning that you are violating the manufacturer's installation instructions to use it on walls, and (b) has a vapor-permeance of only 0.033 perm, which makes it a vapor barrier -- in your case, a wrong-side vapor barrier that could easily lead to wall rot.
Thanks Martin
Was Kind of thinking the same myself. Appreciate the feedback and the website. Great resource. Well done
Peter
Fortunately, Benjamin Obdyke has this note specifically for this situation: http://www.benjaminobdyke.com/uploads/resources/HydroGap_Under_Metal_Cladding_Tech_Bulletin.pdf.
I don't think it's unreasonable for the installer to be concerned--it's no fun to see ice and water shield melting out from below metal roofing. There are now high-temp roofing underlayments made for the additional heat of a metal surface facing the sun, which can withstand over 200°F.