Unvented roof assembly in Climate Zone 3
Finishing up drawings of new single home construction. The attic space will be unvented. Planning on ducts being placed in attic using the Buried and Encapsulated method. Will use loose fill on top of this. My questions are:
1– Should I use foam board (what type and thickness) attached to the roof rafters with insulation (what type) in the cavities, or no insulation inside at roof, or Insulation (what type) on exterior roof deck?
2– Should I consider a raised heel? I have been told that roof needs to be stick built vs. truss system due to complications of roof design.
3–Does vapor diffusion come into consideration with this roof insulation design?
Notes–Planning on using Zip insulated on exterior walls with Zip on roof deck. Exterior will be combination of stone, brick and some stucco
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