Re: Spray Foam Insulation for garage under bedroom
The fact you have your home's heating system tied into the garage is a code violation in areas that I know. Besides .... it's a bad idea as you mentioned ... coarbon monoxide and other fumes can enter the home from this.
In situations such as yours where rooms above garages are cold ..... spray foam is ideal. Not only from the insulating value it provides but also as an air barrier.
The R 11 insulation that exists is probably fiberglass batts and there likely is air from outside circulating inside the ceiling of the garage as well. This moving air greatly reduces the insulating performance of the fiberglass batts.
This is an important part to aid in making the floors of the upper rooms warm ..... providing an air barrier preventing any air movement within this space.
Closed cell spray foam will effectively create an air barrier and high value of insulation .... also it will seal the garage from fumes infiltrating the living spaces above.
Hopefully this helps.
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