I have a 24x36 (inside measures 23x33) 2.5 still attached garage. 8’ ceiling in about 2/3 of it with a loft above. Loft is insulated from the garage so it’s cold up there. The other 1/3 of the garage on the end has a 11’-12’ceiling. Everything is insulated with R13 and 7/16” OSB. My 2 9x7 garage...