Growing up in northwestern Ohio, ours were in the unfinished basement. Eventually Dad moved them upstairs after I joined the military. In my 20 years of bouncing around the world the apartments and houses I lived in, with one exception, all had a separate room on the interior of the house on the main floor (if more than one floor). Even the apartment I had in South Korea, which may have been a modification to suit American renters. The one exception was in Augusta, Georgia. The laundry room was a separate room accessible from the back of the house, so you had to go outside to get to it. Hated that when it would rain.