I don't remember when this started happening (we have been here 5 years) but we keep having a problem with our washer drain overflowing. We have had professionals come out with a snake 3 times, and done it ourselves a couple of times. Each time it's only a temporary solution which lasts for a while but then starts up again a few months later. The first time we realized that it was happening the water has seeped under the floor in the kitchen on the other side of the wall. Since then though it doesn't seems to be coming into the kitchen, but overflows into the garage from the furnace closet. I'm at a loss for what the problem is and how to fix it. Any ideas?