"Scott Mathers" wrote in message
...
I am thinking of adding insulation to our attached garage wall, to
increase the insulation between the living space. Is adding Dow
styrofoam board or something similar a good idea, or worth the cost?
(It's more flammable than the 5/8 fireshield)

For example, the Dow 1" stryofoam board would add R5 to my wall, which
is only 3.5" with R-11 fiberglass.

Thanks guys!

Exposed foam is a fire fuel looking for an ignition source. Please provide
the source for this foam board. with 1" equals R-5... I bet you did not read
the whole listing. This rating is part of an assembly.

More insulation in the attic seems a better bet. I added R-30 this summer
and cut the a/c bills in half from July to August and more than 40% since.