Do any pro drywall contractors prefer to install board vertically on the walls? I haven't seen it done that way much for reasons I thought I knew. I assumed it was because of electrical outlets and switches, header joints at windows and doors etc. Is there other reasons? It would eliminate butt joints. The reason I asked is my neighbor diy guy is building a house and I offered to sell him 6 sheets left over 1/2" 12' rock to get it out of my way. He said he can't use it because he's using all 8' rock on the wall so he can run it vertically and not have any butt joints.