We are north of Dallas TX, and are pulling all the brick and roof off our home (originally built in 70’s and added on to through the years). Several reasons why we are doing this, but prudent here is while it is off what can we do to make the home more efficient. 

The older part of the house is 2×4 and crappy “cardboard” sheathing. The newer is 2×6 with blown in fiberglass walls, sheathed in OSB and wrapped. Windows and door are just builder grade junk so they will all be replaced as well.

Just hoping for some validation that my plan is not crazy.

On the cardboard part we plan on pulling that off and stuffing in as much mineral wool as we can.  Install 7/16 OSB to match the rest of the house. We plan on doing this in 4×8 sections so hopefully the wall shear will be fine and not do any interior drywall damage (we are trying our best to minimize any interior remodeling). Pull off the wrap and apply a fluid applied wrap. I’m leaning toward Prosoco Cat5 given its 12 month exposure. I’d also considered an adhered wrap like aluma flash or deltasa, but given our plan for the attic getting a good seal around the rafter tails seems more likely with a fluid applied. Over that I plan on installing InsoFast 2.5″ to provide some exterior insulation, and a place to install the siding/thinstone. I plan to stop here and hire masons to put on the stone/siding. That’s why I like InsoFast, seems easy to manage as DIY team, and leaves essentially a studded wall for the trades.

The attic will be converted to conditioned space and the central air moved up there, as well as an ERV installed. My plan is to to vac out the layer of blown in insulation, and fill the rafters with closed cell, or possibly 2″ of closed followed by open to save cost. Personally I don’t really trust open cell given its ability to act as a sponge if there were a roof leak. I plan on cutting 7/16 osb around the rafter tails to create a “dam” at the wall/eve. 

I’m still mulling around options on the roof. I’d like to do some insulation there as well, and given that I’m spray foaming the attic it won’t be vented. I was thinking about something like a hunter panel, but haven’t seen the cost yet. Currently we have stone coated steel roof and we love the look and durability, don’t love the fact the company went out of business and we cannot get matching panels anymore (hence another reason to re-skin the whole thing). Would love some ideas here. I’d go stone coated again, or synthetic, or possibly metal, but we are a high hail area so smooth metal shows dents. I’ll stay away from asphalt it is a relatively low slope and even top tier shingles blow off.