Meet R-Values and Stop Heat Leaks
Sloped attics challenge insulation depth and continuity. To reach code R-values, combine cavity insulation with a continuous layer that breaks thermal bridges at rafters. Common stacks pair high-density batts or spray foam in the bays with either rigid foam above the deck (re-roof scenarios) or continuous insulated panels below the rafters. Maintain an unbroken air barrier and seal every penetration—top plates, skylight shafts, electrical boxes—so your R-value performs as designed.
Dew-Point & Moisture Safety
In unvented assemblies, keep the sheathing warm enough to avoid condensation by meeting the required ratio of exterior to interior insulation. Use vapor-smart membranes on the warm side, and document cut sheets with labeled R/U-values for permit reviewers.
Details that Pay Back
Thermal break the knee-wall caps, rim joists, and skylight returns; specify insulated attic hatches with compression gaskets. Commission with a blower-door test and duct leakage check to verify targets before drywall.
For assembly diagrams and material options, explore our energy-efficient attic remodeling in NYC guide.