I am having some drainage problems with one section of my new old house. There is a 1.5" pipe that attaches to the laundry tub in the basement and the kitchen sink above it and then exits the house through the roof and through the wall/floor. I attached a diagram of this specific pipe. There is a separate much larger main drain that services the bathrooms and has no problems that I've discovered... yet.

My problem is that the laundry tub drains very slowly, almost imperceptively slowly. The kitchen sink drains alright if I just run the water, but if I fill the sink and let it drain, about half the water leaves and the rest escapes at a trickle. When the kitchen sink finishes draining there is a "glub glub" sound and it appears as though water is being sucked out of the trap.

I'm having trouble figuring out if it's a venting issue, blockage in the drain or what.


http://img694.imageshack.us/img694/4413/diagramg.jpg

Sorry, here is the diagram... I couldn't see my attachment.

I would start by snaking the pipe on the roof. Put in enough snake to get to the basemen floor, then another twenty foot just to be safe. This should cure your prblem, as it will clear the vent and drain for both fixtures.

You have problem with your vent follow Mygirlsdad instruction, goodluck.

John

Both experts are correct. The "Glub-Glub" that you hear is the sink venting through the trap. This just screams "blocked vent". Follow Dads advice and consider changing the drain line from the kitchen to 2" PVC all the way to the main in the basement. Good luck, Tom