I have a short living room wall (4'tall) in my split level exposed to
garage and thus to outside temps. Would like to insulate at lowest
possible cost. Looking into injected foam, way too expensive and the
material is not economically available for DIY. I have seen, on this
old house, contractors drill holes near the top of walls between each
stud and fill with cellulose, blown in. Sounds crazy, but what about
this:
Drill same kind of holes, then slowly fill with popcorn packing
material, NOT the water soluble kind. Free material, shipped to me all
the time. Should last forever.
Any drawbacks anyone can think of? Is this stuff particularly flamable,
so not suitable?
I could also apply foam board to the outside of the sheetrock (garage
side) and cover that with plywood, but with that air space between the
studs, I'm not sure this would do any good.
If I can get even r-10 or so, I'll be happy.
Any advice would be much appreciated.