When we originally built our home, we finished the bathroom and laundry room floors in our hillside walk-out house with off-white vinyl flooring of good quality. There was also the proper subfloor installed underneath. Within the first year, due to dampness of the concrete floors, greying started appearing under the off-white vinyl. Within a few years, it had spread to the entire floor with splotchy grey areas all over the floor. We have to do something with this floor. I have an idea to purchase ceramic tiles like the ones with about a dozen earthtone colours in it. Perhaps then we won't see the grey of the concrete pushing it's way up due to moisture. By the way, we added a heat exchanger a few years ago, whether that would make any difference or not.