Water Managed Roof – Re-roofing and Adding Insulation Over a Sloped Roof Description Guide describing how to re-roof an existing home with a sloped and add insulation above the roof deck.
Above Deck Rigid Foam Insulation for Existing Roofs Description Guide describing the installation of insulating sheathing above the roof deck on existing homes. This retrofit assembly is appropriate for homes with conditioned attics or where the retrofit is intended to create a conditioned attic.