Making a frog energy efficient
I am converting the bonus room over my detached garage into an apartment. Extended dormers are being added on the east and west sides.
I've read that this apartment has the potential for huge utility bills if it is not insulated and sealed properly.
I've asked the builder to air-seal the room as well as use a radiant barrier. I can see that the contractor is using thermoshield for the roofing but doesn't appear to be using it for the walls. Should I request a radiant barrier be added to the walls?
I'm considering asking for spray foam insulation instead of fiberglass but have been told that it is 3 times the cost of fiberglass.
Is there a compromise that perhaps a combination of spray foam and fiberglass could minimize my utility bills without costing an arm and a leg? For example, a 1 inch layer of foam AND fiberglass batting or foam for the garage and apartment ceiling and fiberglass for the walls?