Putting on new roof to add living space.

We've seen a couple of neighbors in our very rural area just totally replacing their roof with one with enough pitch to put additional rooms upstairs.

We are definitely going to talk to them about the planning process they went through and any information on problems and solutions they had and of course the pros.

I would love to have your input as all views, facts and opinions presented on a multitude of questions on here leaves no stone unturned.
Our 30 year old house is 60'X30' with 20'X30' of that having a vaulted ceiling 4' high.That leaves 40'X30' with 8' ceilings. There is a 5' porch across the total length on the front.
The roof on this part has gables on each end with the storage room and laundry room sticking out the back 30'X12' and carport 22'X32' behind that with a gable at the back.
We may decide to keep the valted ceiling leaving the 40x30 for replacing.
Including the30x12 storage is probably a natural to be included because of tieing the new roof in.
What would be the steepest roof that would be acceptable for appearance and structural concerns.
Hip roof or stay with gables.
Do I have enough support to even think about it. I have 6" rafters on 16" centers.Here's a picture I already had. If it will help I'll take some more.

Thanks, woodchuck

Sorry but I don't think that 6 inch rafters is enough, if i remember correctly what I have in my basement is 2x12" with a span of only 12' on 16" centers. If you are willing to go to all the work of putting up new 2x12s then go for it, you would also need a center support for the new floor upstairs.

I don't think it would be an effective way to go
Justin

I have now been looking at what I can find about joist size. The 6x2 that I have can have a span of just over 9' to meet the flexibility spec.
So I have two bedrooms that are at least 12x12 and another around 17x17. With that span would there be a header or something in the attic that reduces that span.
If all the spans are the right length would the 2x6 support a bedroom.

Hello Woodchuck:
I would consider the new I-beam OSB joists for the second floor to sit on. You can get them in a size that will support your load at whatever span you want. You would need to go to a 6/12 pitch at a minimum to make any space in the attic. Or you could make a 6/12 pitch on the front and a 2/12 pitch on the back to cover a dormer which would allow you to double your space.
I would stick with the gable roof line to utilize the space to the end of the house.
I am considering you having trusses supporting the present roof and would have to do a complete tear-off of the section over the bedrooms, while the vaulted portion probably has scisors trusses.
Glenn