R-49 attic insulation is recommended for this climate, and I spec R-60 for most attic floors because cellulose is cheap. Yet my own unconditioned attic has an effective R-value of only about 20. There is a typically settled loose-fill cellulose job from the early 80s under the floorboards. I decided to relocate the thermal boundary to the top of the loose tongue-and-groove attic floor…
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