Roof Decking Compatible With Light Gauge Steel
Hello all,
I’m building a 10×36 tiny house using light gauge steel (CFS).
I’m planning to use Zip insulated R-sheating on the exterior walls, and I was planning to use the Zip roof sheating for the roof deck, however, as I was reviewing the installation manual I read that you are not supposed to use the Zip roof sheating on roofs with slopes less than 2/12. My tiny house has a shed roof with a 0.5/12 slope. My plan is to use standing seam metal roofing.
If I can’t use the Zip roof sheating what are my best alternatives?
Also, the house is being built for zone 2 possibly zone 3 and I would like to get some advice on the roof/ceiling insulation, more specifically what should I do for thermal bridging on the roof. My plan is to use rockwool insulation on the walls and ceiling.
Thank you in advance
CG
GBA Detail Library
A collection of one thousand construction details organized by climate and house part
Replies
I 'll keep it short because...
Skip the zip roof, use plywood instead, high temp Ice and watershield, standing seam roofing. Dry toward the inside, with this approach. Walls proceed as you planned.
Thank you
I would also add on there, that with CFS, you loose about 1/2 the R value of insulation because of the thermal bridging of the studs. So if you want a roof that provides some real amount of insulation, I would put at least a layer of rigid ontop.
So in that case the roof would be:
-drywall
-CFS studs with batts
-plywood (taped seams for air barrier)
-rigid insulation (as much as you have height for, 2" to 4" )
-underlayment
-metal roofing installed over 1x4 strapping
Thank you. I have a height limit on my build and adding the rigid insulation may be a problem since the frame has been manufactured already.