I have an idea about building a floor joist that would look super cool from below.
2x6 in the middle sandwiched with a 2x4 on each side, and then a 2x2 on each side of that. Screwed and wood glued it would be the equivalent of a joist that was like a foot wide, the arch/stair step structure taking the load down to bottom of the main beam.
Best part is that these beams could be pieced together, the main beam with two bolts with washers and nuts pulling the board together at the top and the bottom. The 2x4 and 2x2 could just be lapped, as long as no seams lined up within about a foot. Also lower grade would can be used, as long as bottom edge is free of knots.
