Wayne Whitney wrote:
....
One simple option, depending on clearances, would be add two more
girders (support beams), to reduce the joist span in half. But this
would only be a good option if you could avoid further notching of the
joists.

Actually, that's a most excellent idea, Wayne...

And, if it is crawl space, could simply pier it in a few places (every
other or every third, say) and not need to worry about the height issue.
Would need an adequate base for each pier, however, of course...

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