It is just a 1-Story house but the other bath rooms are on the other side of the house and working fine. Never have problems with them. There is no crawl space or basement and I think it is on...
We don't have a shower or bathtub there. It is just the Guest Bath in our Laundry room. It takes a while to back up in the toilet. And sometimes the water stands in the dish washer.
We bought a house 7 months ago and since 4 months the toilet would overflow if we use the wash machine, the dish washer or the sink in the kitchen or bathroom. I would see the lint from the washer...