Re-roofing an unvented Vaulted Ceiling/TJI/ Spray foam roof. Is it smart to add furring strips and another layer of sheathing to create an air gap/ventilation channel?
MikefromtheMountainsofUtah
| Posted in General Questions on
I’m in the mountains in northern Utah and my home is 1998.
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With spray foam insulation, ventilation is not required by codes, and in most cases the roof will perform just fine without venting. In fact, venting can be a negative in the event of a wildfire or sometimes with wind and moisture events. In other cases, likely including yours, venting would add a little resilience, allowing any moisture in the assembly to dry, and keeping the roof surface cold enough that icicles and ice dams shouldn't form.