Exterior Wall Insulation

Retrofit Batt Insulation, Outside Walls

I have insulated the outside walls in one room of my own home. I have known I would tear down interior drywall, to properly place batt insulation, as I did thirty and thirty five years ago in my previous homes, in Connecticut. This time I have access to much better materials.

The method includes removal of window trim, for concurrent window replacement, and saw cuts 1 1/2" away from ceiling and from baseboards.

The found walls are tight, with 1" thickness R2.4 Celotex sheathing. Further, they are complex, with diagonal bracing that would have made a loose-fill blow ugly, and destructive to the value of the home, with its irreplaceable, wide, old-growth cedar siding.

I brought down new electrical and data wiring, from the attic, nearly completing that job at last. Wiring upgrades are difficult in exterior walls, and get a lot harder after insulation fill.

The new batts are Johns Manville U1319, R15 15" x 93". Total material applied is 106 sq ft.

Swedish Tenoarm vapor barrier, age-resistant and 8 mils thick, is sealed to full perimeters of walls and windows, with 3/4" width double-backed butyl tape. The Tenoarm, 9' 2" width roll, and tape, were purchased from Resource Conservation Technology.