What is the best way to insulate a 2x4 wall from the outside in a cold climate?
...insulation, spray foam cavities from outside in, reinstall plywood (might be some air gaps behind plywood), add tyvek drainwrap wrb, then add 2" polyiso enerair, 1" strapping, siding.
2. Remove existing plywood and cavity insulation AND existing poly vapor barrier. Install rockwool batt insulation with NO vapor barrier...