Roof framing is important! After all, the last thing you want to have is a house with a leaky or unsafe roof. This is why you should be extra attentive when it comes to this important step.
Be sure you are using the proper size rafters and spacing to handle the design loads. If the proper material and spacing is not used, your roof may sag under heavy weather loads. All ceiling joists and rafters should be tied together and to the top late by using hurricane straps/clips weather required or not. Roof decking is an area a lot of people cut corners on but wish they hadn’t later on.
The material and size you use will be partially determined by the slope of your roof, the load you are trying to achieve and the spacing of your rafters. I don’t think you should space rafters more than 16” on center and I prefer to use 1x8 for my sheathing. This gives me a very strong flat surface to nail my roofing to and I don’t need to worry about sagging in severe weather – snow, etc.
Most common roofing calls for 15 lb. felt to be placed on the roof deck prior to applying the shingles. This is the approved method, however 15 lb. felt is very susceptible to wind damage. If you get a good rain storm or high winds before you put on the shingles, it will most likely be severely damaged. I prefer to use 30 lb. felt, as this will hold up to most wind storms.
Proper roof framing will give you a sturdy, secure home that keeps the elements at bay.