With your tremendous liability in a commercial application, I suggest a Structural Engineer. Add it to your insurance policy, too.
TJI's are rated for loads and approved by Building Departments at the time of construction. The joists are doubled or tripled, depending on load. The gaps in the webs are filled with plywood, as well as outsides. Then the hanger, rated for the load, is installed with nails or special screws.
Your joists are rated for what they are carrying now, no more.
I don't see any application feasible without hiring a S.E. first. Be safe, GBAR
TJI's are rated for loads and approved by Building Departments at the time of construction. The joists are doubled or tripled, depending on load. The gaps in the webs are filled with plywood, as well as outsides. Then the hanger, rated for the load, is installed with nails or special screws.
Your joists are rated for what they are carrying now, no more.
I don't see any application feasible without hiring a S.E. first. Be safe, GBAR