I'm building a 30' X 40' insulated woodshop. Walls are 2 X 6. Bottom chord of the ceiling truss is also 2 X 6. We live at 5700 ft and get temps down to 0 sometimes in the winter.
I have two questions
1) If I use R-30 in the ceiling, the insulation is 9" thick and will be 3 1/2" higher than the top of the chord. Is this overkill or inefficient if I don't plan to use blown in insulation between the batts (over the 2 X 6 chord)?
2) The center section of this shop will have attic storage so I'm adding an attic floor (5/8" OSB). If I use R-30 in the center section, I will have to compress those last 3 1/2" of insulation to keep it between the ceiling sheetrock and the attic floor. Is that more effective than using R-19 in the ceiling in the center section?
Thanks for any feedback.......