I'm building a 19ft. wide garage and would like to use 2X6 rafters with a 2X8 ridge beam. The way I'm reading the span table for a minimal load, I believe it is telling me that I need 2X10 ceiling joists. I have a 5 psf snow load and I might sheetrock the ceiling, but a 2X10 seems like overkill to me. I'm thinking it's sized to control deflection or the sagging in the middle. Does anyone see a problem with 2X6 ceiling joists and a couple of 2X4 vertical ties to a 2X4 collar tie ? Or does anyone know of a website with plans for a stick built roof? I'm trying to stay away from trusses if I can.