I think I might be on to something...roof covering idea

Hi everyone, I've been carefully planning my impending build of and I've learned that other than the 3/4 plywood for the floor, finishing the roof to be weather tight is going to be the single most costly thing. So any way, the other day I was helping my boss unload this big canopy and thought; maybe I can use this material for my roof coating! Big white tarps are easy to get on a budget. maybe...just maybe i can glue it down to primed wood with liquid nails smeared evenly and then trim the edges flush before installing molding. I'm trying to avoid seems. Does this sound possible? 
