In article ,
Roy J wrote:

Downside is that the shop level has to have posts to
get in the way

Not for certain, these days. The second story on my shop is designed for
50PSF (actually comes in about 56) and clear-spans 22 feet 8 inches. I
did have to special-order some serious I-joists to do that, but it beats
having posts in the lower level.

Dad did a similar span with gluelam beams and regular joists from beam
to beam - depends what you can get at a better price in your local
market, at a given time. Steel may be cheaper in some markets.

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