Second floor header

[Chris]

I'd like to add a 22'x22' second floor to my garage which is 22x32'. (2x6construction) the floorjoists would run the 22' direction and the trusses the other. This means that 10' into the garage a load bearing header would support the roof trusses and one exterior wall above. Each of the other three walls would be bearing on the existing exterior walls. Could I use header calculations similar to a garage door to size a header below? A 17' clear span would be nice and unobtrusive and I have slab heat and am also wondering about post support needed? Any thoughts appreciated.

[Rich]

If you look at www.trusjoist.com and look at their parallam or microlam beams you will want to look at the roof and floor loading together. They have several different loading conditions just make sure it covers floor and roof.

[mjpliv]

By the description of your project I am assuming that there will be a wall projecting above what will be left of the old garage roof. If this is correct, be sure to factor in a snow drift load when calculating the beam size. This should be based on the height of the wall. Most suppliers of Paralam (PSL) or Microlam (LVL) beams have someone on staff who can size the beam properly for you.