I’m adding a golf simulator to my basement.  The height from the floor to the bottom of the ceiling joists is an inch shy of nine feet, and it’ll be around 8’8″ after the flooring is installed.  I could use a few more inches (my wife would agree!), and I’m trying to understand what my options are in terms of recapturing space from my ceiling joists.

There’s a home office immediately above the room in question, and the joists are 11-7/8″ LP engineered i-joists (16″ O.C. and span is 14’4″).  I’ll obviously have a structural engineer sign off on anything, but, before I go that route, is it feasible to replace several i-joists with, say, 6″ steel i-beams (thus freeing up almost six inches around the swing zone), flitch beams, etc., or is the span too long to meaningfully reduce joist depth?  Thanks.