Hey Guys!
It is a single story house with a roof pitch 4″ in 12″ and 2×6 rafters, @16″ o. c.
The footprint of the space under the roof is 28′-0″ x 28′-0″.
The height to the top plate is at 7′-10″ and the exterior walls are standard framing with 2″x4″s and 16″ OC.
There is a 28″ crawl space with a rat slab and 15″x15″ CMU blocks foundations every 48″ supporting the floor joists. The only roof loads is the plywood sheathing with asphalt shingles.
Please note that the existing roof ridge and rafters do not have rafter ties or collar ties
Basically looking for advice on: see images below.
1. Option A, add (2) girders: Can we add to girders 30″ or 47″ offset from the ridge? What approx size beams, 2×12 LVL? What sizes?
Should the rafter sit on top of the new beams, or attach with lag screws?
2. Option B, center column: Can we have one (1) column (shown as 7.5″ square) to adequately support the ridge beam? What size of columns to support the ridge beam and foundation size 24″x24″? Can the beams be in sections above column? better with two smaller beams bolted together at the column? Or does it have to span all the way across? Also the column, does it need to go to the ridge as one piece or should the beams sit atop of the column?
We will reinforce the exterior 2×4 wall with LVL under the top plate above door headers. Sizes?
Thanks!!!