This is the framing for the floor. It is created here with true rough cut 2 x 4’s and not milled, planed, dimensional 2×4’s (1.5 x 3.5’s). Anyway, it’s my first real attempt at Google Sketchup, and I think it went pretty well. Still a lot to learn.
The dark lines are where the floor sheathing plywood would hit every 4 feet. The studs are 16″ OC usually, except the one in the middle is like 21″ or something. It’s just so that it hits the sheathing, which is a good thing.