ceiling leaking in basement laundry room

hi everyone,

this my first time posting on this site as i've usually found the answers to my questions without having to do so (this site rocks!) but i have recently come across a problem that i cannot seem to find a solution to.

our house was built in the mid '80s and we moved in about 18 months ago. anyway, about a month ago we started noticing that the ceiling downstairs in our basement laundry room is leaking. i think i have narrowed down the source of the leak to be coming from either the dishwasher or the kitchen sink (do they use the same pipe to expel waste water? if so then i think it's that).

our faucet had been leaking so we totally replaced it just last night and we stopped using the dishwasher as it does seem to leak quite a bit when it was run and thought that we had solved the problem, but when we were running water though the new faucet to flush it after setting it up we noticed that the ceiling was leaking again but when i ran the sink this morning just to see what would happen it didn't seem to leak at all, but maybe i didn't run it long enough or something

is there a way for me to be able to tell exactly where the leak is coming from? is it pretty reasonable to assume that the leak is relatively close to the damage? it seems to me to be starting near the wall in the direction of the kitchen but just looks worse where the weak part of the ceiling is (the seam in the drywall). also the pipes have started squealing around the same time we discovered the damage (maybe a little before, because it probably took a little while for us to notice the damage) could the two be related?

any insight would be wonderful

thanks! zephyr78

 

Your dishwasher empties into your sink, possibly with an air gap, so yes, they share some piping. However, there is a drain hose which carries waste water from your dishwasher over to the sink drain line, this could be leaking. If you can't see a leak in the kitchen itself (checking everything under the sink and dishwasher, then the leak may be in the waste pipe in the wall. It's tough to diagnose it without tearing into some drywall and seeing what is going on.

I assume the underside of the first floor isn't visible, or else you'd probably have found the leak by now. I'd recommend starting there, since you'll probably have stained, soggy drywall you want to fix anyway. If it's not an obvious leak from the sink's p-trap or supply lines, then I'd start diagnosing it from the basement up.

 

thanks arniebuteft, for the response.

there is no leaking in the kitchen at all (at least not since replacing the leaking faucet). and we cannot see the underside of the floor, unfortunately. we were thinking we'd have to tear out some drywall (as we do need to replace some anyway) but it's good to have a second and undoubtedly more knowledgeable opinion.

just a question, would the crawl space on level with the basement floor be a better place to start than in the basement ceiling where the damage is?

thank you again,
zephyr78

 

Since you'll probably have to replace the basement ceiling anyway, try pouring some light colored (lemon aid?) Kool Aid down the sink and see if the ceiling turns that color. Then pour a little red Kool Aid in the dishwasher and see if the ceiling turns THAT color. If it only turns one or the other, that tells you which one is leaking, If it turns both colors, then its probably inside the wall after they join up OR you really have two leaks.

I think no matter what you're going to be tearing out drywall.

Good luck,
Tom