Would love to see an application for an existing floor joist of solid sawn to be reinforced with LVLs to strenghten the floor for tile load use or increased live load loading due to a project renovation.   Some projects require an existing floor joist such as a 2x 8 to now carry a tile floor with a mud setting bed, which adds additional loading on the existing joist.  Based on the spans if a doubled up joist doesnt work the program could easily show if (3) 2x 8 fj would work, and usaully does, there if no way or calculate the mixed use of solid swan and lvls to show a mixed solution to adequately carry the loads and meet deflection criteria of ceramic tile l/480 or stone flooring l/720 . 

How about a combination of solid sawn member (2×8) with a 7.25″ lvl to see if that work work?  For alot of us doing renoavtion work this would be ideal… 

I only depicted 2×8 and 7.25″ lvls as an example.  It could be any depth member and lvl in matching depth to keep it some what simple for the program to handle. 

Any ideas?