Can a defective studor vent cause water to leak from the waste pipe when the dishwasher is operated.

We had an addition put on that moved the kitchen 10 feet out 7 yrs ago. Recently I noticed that the engineered wood in front of the dishwasher turned black. Plumber and diswasher repair guy said it is not the dishwasher or the pipe connecting the dishwasher. A leak detection guy came out and tested the water pipes and did not find any leals or loss of pressure. We cut through the subflood under the dishwasher and found a puddle that was on the cement slab between joists and under the sprayed in insulation. No one can figure out how the engineered wood got damp as it is above the subflooring, plastic vapor sheet, and 1/8 inch cork underlaying the engineered wood. Ever heard of such a problem?

Dave

Herndon, VA

Hi murphdjm3

Run the dishwasher and see if the studor vent leaks... right? The studor vent itself can open and discharge water if defective so definitely check that during a drain cycle and be sure to have a flashlight and paper towels handy to check for even the smallest leak.

Otherwise, water can also come from outside somehow and sit in an environment like you mention for quite a long time, so I have to figure that if a leak detection company came in and couldn't find the source of the leak INSIDE the home then it is probably getting in from outside via rain... just a guess.

Question? Besides the engineered wood, was there any signs of water damage to the subflooring, the vapor sheet or the corkboard where you made the cut in the floor or was everything dry until you got to the cement? Let me know.

Mark