I am new to posting but have been reading for a long time.
I am redoing a 16x24 pole barn in nothern Michigan (heavy snow loads). Here is my problem: I want to put in a ridge beam, 2x10, to span 24ft with no center poles so my rafters would be 2x6 16 o.c. and span half the building width approx 8' and my collar ties (if that is the proper name????) would be 2x4 @ 1/3 height of the 6/12 pitch measured down from the peak. Will this work? Is it over or under engineered?????
The 2003 I-code requires the ridge to be supported like a beam if the rafters are not tied at the plateline (ceiling joists) at 48" o.c. to resist the walls thrusting outward under roof load. Not sure if that changed in 2006 however.
A 2x10 will not span 24', or even close to that under the loads you're dealing with. You're under-engineered I'm afraid.
By tying the rafters together tail-to-tail across the building, you really minimize the load on the ridge. A structure that is tied at the plateline could (technically) be framed without a ridge at all, because the ties resist the ability of the ridge to move downward and thrust the walls outward.