Need Help With Loft Building

[jrob80]

I'm getting into the tiny house movement need help with doing lofts. This is what I have so far for first floor just playing around at the moment getting the fill of it. It's going to be 10x20 200sf have gable roof another. ? would walls for my bathroom which is the only room I have do they have to be all the way to the top to place floor for loft. Either words could I make the loft a bit taller then just a sleeping crawl space not my much though.