G'day, Need some advice on the best way to re-insulate my home during a large scale renovation I'm doing next year. The critters have come through the old siding (knot holes, cracks, warping) and perforated the house wrap, and tunneled in the insulation. My home is a nightmare to heat and cool. First thing you need to know before you offer advice is that my home is double wall construction on most of the walls. So - from the inside of the house to the outside of the house - these are the layers... 1) 1/2" drywall 2) 2x4 studs insulated with 3.5" Fiberglass pink 3) 6mil plastic vapour barrier 4) 1/2" OSB 5) Insulated dead space - 2" I believe 6) 2x6 studs insulated with 5.5" Fiberglass pink 7) Tyvek or equivalent house wrap 8) Wood bevel siding My initial thoughts are to: 1) pull the outside of the house off - until I get down to the OSB that is sandwiched between the two walls. 2) Put down an inch or two of spray foam into the dead space between the two walls (on top of the OSB) - primarily to air seal the envelope. 3) Re-insulate the 2x6 stud wall with Roxul. 4) Put another 1/2" OSB layer of sheathing on the outside of the house - primarily as a rodent / bird barrier (little buggers). 5) Re-wrap the house in a Tyvek or equivalent house wrap 6) Re-side the house with a horizontal siding that incorporates at least some form of mechanical joint between the rows (tongue and groove, channel rustic, etc.) So - my questions: 1) Am I nuts or does this approach make sense in general? 2) Yes to spray foam that way, no to it, or change where it is in the layers? 3) Does any type of radiant barrier make any sense instead of, or in conjunction with - the house wrap? I get one shot at doing this while the whole outside of the house is peeled off. I want to do this once and do it right. Another side note - all of the outside windows will be replaced at the same time is this tiny little project. Sean.