Is wallpaper sq feet calculated differently than other things. I notice online that a specific one that I like covers 30 sq feet. The room I'm covering is 14 by 12 and 8 ft walls. I calculate that at 416 sq feet of wall space. Sure, there are doors and windows, but that is the basis measure. Does that mean I'll need 13 rolls, and at $40 a roll, it's going to cost $520 just for paper for one room? Am I calculating incorrectly? That just seems like a lot.