We often have people asking us about bad smells coming from their drains. For many, they’re worried that the smell is a sign of an impending backup because they recently dealt with one. If you’re in a similar situation, the good news is that it’s not a guarantee of another backup. This article will go over another common cause of foul smells coming from a drain that backed up before. We'll also go over ways to address the smell.
Your main drains work like a waterslide angled down and away from your house. It drains waste and water into your municipal sewer system. When you flush your toilet or water goes down the drain, it flows through the p trap and into the main sewer line. The water runs along the bottom half of the pipe, allowing room for displaced air in the top half of the pipe.
That p trap has a very important job. It’s there to hold water at the bottom of a dip in the pipe. That water seals any sewer odors or gases behind it so that they don’t find their way into your home. If you have a drain that you don’t use often, or if the p trap breaks, the water may evaporate or leak out of the p trap. If that happens, the seal may fail and those odors could start leaking into your home. On top of that, bathroom sinks tend to have gunk get caught before it even reaches the p trap that can start to stink if it sits for too long.
If your pipes smell because there's gunk trapped in a drain before the P-trap, you can take it apart and clean it. It doesn't need a lot of tools and only takes a few minutes. You can check the link below for a video walking you through the project. This can be a bit trickier for things like floor drains or shower drains, so you might need a hand from a drain tech in those cases.
If the smells come from a drain that doesn’t get used very often, you can pour a bucket of water down it in case the water in the p trap evaporated. That should refill the p trap and seal the pipes again. After that, it’s a good idea to run some water down all of your drains every once in a while to keep the water from evaporating. If you notice a leak when you try this, you might want to have a plumber help you fix the problem.