I own a chicago style brick bungalow. I am going to put a bonus room in 1/2 of the attic. I am going to put down 1/2 " osb for a subfloor over 1 x 6 floor joists. i am going to build 2 knee walls down the length of the room and hang 3/8 inch dry wall on 2x 6 roof rafters
16" on center. Do I have to double the roof rafters to carry the increased load
Thanks,
Jim