I am building a 24x32' 1 1/2 story 5 bent 4 bay wood shop. Can you help me size the tie beams and floor joists. I am using 1x12's on the attic floor and would like to cover these with 4" sips and use the attic for general storage. The timber frame design is called a high posted cape. I am trying to size the tie beams and floor joists. I would like a clear floor span of 22'8" with no posts and also attic storage with no trusses. I would like a door in the gable end so no king posts. From what I have read the general rule is 16' spans. If I have to add posts under the tie beams to span the 22'8" can they be shifted from the center of the building to the outer wall so I would have a 16' span, a post and an 8' span? I am using the Timber Frame Joinery and Design Workbook, copywrite 1995. I am trying to figure out beam deflection, the formula ^=5wl(4) over 384 ei, will this give me live loads at 40psi? Am I on the right track? Per my calculations for the tie beams in #2 white pine, 22'8" was off the chart. 16', I would need a 7"x12" and at 12' I would need a 5"x10" beam. Does this sound ok? Once I have the beam deflection size figured out, when I cut the mortises into the tie beams for the floor joists, do I add the depth of the mortise to the tie beam size? Any replies would be greatly appreciated, thanks,John. I have decided to sacrifice attic space for floor space. I am designing a truss system . Thanks to all for your help. John.

[This message has been edited by John Milburn (edited 09-26-2001).]