We've lived in our 90-year-old home for 4 years. We have a basement bathroom with shower, toilet, sink. The bathroom is on an 18-inch platform.
Last New Years Eve, water flooded the basement from underneath the bathroom, probably 20-30 gallons. We suctioned it out, no further problem. A few weeks later, it did it again. A few weeks later, again. At this point we called plumbers out to take a look, and they could find nothing wrong, and had no explanation for what was happening.
A few points:
1) The water is cold, not hot. My first thought was the water heater (which is also in the basement, in another area) had spilled, but that's not it. 2) The water is clean. There is no smell or debris in the water. (No toilet overflowing, etc.) 3) It floods all at once. We checked for some kind of leak that might be building up, but there was none. 4) The flooding happens at night (or very very early morning), so the water is not in use at the time it floods. 5) The flooding is irregular; that is, we can't predict when it's going to happen. 6) We had not had the problem for 3 1/2 years....why did it start now? No construction or anything like that going on.We need some advice on how to stop this flooding; it stumped our two plumbers (who seemed competent in all other ways.) Thanks for any help.