I have a relative, that is a contractor, installing a drywall ceiling in my basement that will enclose some of the pipes from the kitchen. I did some web research and noticed that it is recommended that the drywall be installed perpindicular to the joists and that the ceiling be dropped just enough to accomodate the pipes that run beneath the joists. He has the drywall running horizontal with the joists and plans to build a "drop box" around the pipes. I also noticed that he did not use any adhesives just screws to mount the few drywall panels he finished today. Will it matter if the drywall is run horizontally and should I be concerned with this install altogether. I am beginning to question just how many ceilings he has installed.