I have a deck on the front of my house, it is 31 feet wide 16 feet deep.
I have decided to enclose the deck and put a roof on it, just make a big enclosed covered porch. I found a guy to help me frame it out and he has 35 years’ experience building and seems to know his stuff.
To match existing roof lines the new roof will be a 4-12 pitch hip roof.
The common rafters will need to extend the wide part of the porch, the 31 foot portion. This contractor said he would use 2X6's for the commons 2X8s for the two hips. He also said the ridge rafter could be a 2X6 because it isn’t structural, he said it is just to line up the commons.
My question is, are 2X6's adequate for 18 foot commons? I am in SW Oklahoma and there is no snow load.
He also said we would do 24 in OC and he said that would be good. I thought 16 OC would provide more strength?
He mentioned collar ties but didn’t say anything about rafter ties for the lower third portion of the rafters. I would think these ties would be crucial to prevent the walls from bowing out?