I am removing a wall that splits a room that spans 24' , and is 22' long and carrys the weight of a standard 1/2 drywall over 2x6 ceiling ( 8') joists 24 " O.C., with a standard 2 x 6 rafter 24 "O.C. at a 4 & 12 pitch with a 40 yr. comp roof. what size LVLs do I need and how many sandwiched together ?
You may need a permit from your local Building Department for this structural change. They will want to see the Engineer's stamp and notes for the size of LVLs, strapping attachment for shear flow and uplift, post sizes, footings under the house or under the basement slab, possibly added shear panels of plywood to make up for the removed wall, etc. He/she will take liability for the beam during and after you install it to minimum safety code. The paper trail is good for your H.O. Insurance carrier also.
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.