Two questions here. First, I am enclosing a garage to use as a bedroom. The existing exterior walls are built on foundation "walls" that are about a foot high and wide. I erected new walls right at the base of those foundations to give the room a cleaner look. Wondering if it would be an issue to insulate both the existing and new cavities. I live in SE NC, so I'd probably use unfaced for both.
Next, in regards to bedroom window egress requirements, where do you measure on the window to check the opening dimensions? Specifically for the height, do you put the tape on the sill or the highest portion off of it such as the inside stop?
Yeah you can insulate both, might not be worth the extra cost but you can determine that.
Use unfaced on both walls and install a vapor barrier on the inner face of the inner wall then drywall.
As for the egress you need to measure the actual open area of the window in question.
A min. of 5.7 sq. ft. of opening, min. 21" net clear wide and min. 24" net clear height.