Insulated Roof Questions
I have a 1910 house, 1-3/4 story in Denver, CO (zone 5b) with an unfinished attic. The insulation on the attic floor needs to be increased. My roof is getting old and will need to be replaced soon as well. I’ve been reading about adding rigid insulation to the roof, which sounds appealing since the attic doesn’t cover the entire upstairs, but have a few questions:
1) How would the cost of adding insulation on the rook compare to having it blown into the sloped part of the wall and adding insulation on the attic floor? I just read Joe Lstiburek’s article “Over-roofing: Don’t Do Stupid Things” which showed that it is more than just throwing rigid insulation on the roof.
2) The house is brick on the 1st story and stucco on the second. The stucco needs repair/replacing. Adding rigid foam to the exterior would create an overhang where the stucco meets the brick. Would spray foam on the interior work better?
3) I would like to add central air to the house, but lack return air ducts on the 2nd floor. I may add these in when I remodel the kitchen. Would having an insulated attic make a difference for return ducts?
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