re: Spray foam insulation

I can’t give you a cost since I used spray foam on my house 8 years ago. I sprayed foamed my exterior walls, laundry room walls for soundproofing, and a couple of inches in the attic floor to seal ceiling penetrations. I used blown cellulose over the bottom 2” in the attic to obtain desired R-values.

Couple of things I learned:

1. There needs to be fresh air introduced into the duct system.
2. For new construction, the spray foam will expand beyond the studs. They uses a milling machine to mill off the excess so as to be flush with the studs. But the spray foam can push out wiring or PEX so that this milling machine will damage it, Care shall be used while milling.