Q: I've noticed a rotten smell coming from my bathroom lately and can't figure out the source. Do you have any idea what could be causing this lingering odor and how I can get rid of it?
A: Sewer smells in your bathroom can result from a few different issues, so you'll need to spend a bit of time in the room to sniff out the source. Once you've identified where the odor is coming from, the fix will probably be easy for you to tackle on your own.
It's smart of you to address the offensive odor right away, though: In some cases, inhaling high levels of sewer gas can lead to health problems. Prolonged exposure to sewer gases can cause nausea, dizziness, and, in the case of hydrogen sulfide poisoning, even fatality. Extreme buildup can trigger an explosion.
What's more, airborne pathogens can creep in when the seal that keeps out sewer gases has been breached, leaving you vulnerable to sewer-dwelling germs. Before you start sniffing around, be sure to slip on a painter's mask so you don't breathe in toxic fumes. Then, take things step by step.
First, check for clogs.
This is the fastest problem to fix, because all you'll need is a bottle of drain cleaner from the supermarket or hardware store. Pour it down the shower and sink drains to eliminate any gunk that may have built up in the pipes and caused the stink. Carefully follow the instructions on the packaging, and make sure you wait the requisite amount of time before you flush the drains with water. If the odor disappears after a day or two, then congrats! You're good to go.
If the problem persists, look for leaks in your sink plumbing.
Check for standing water on the floor or cabinet base beneath the U-shaped pipe (the P-trap) under the sink. Also, run your hand along the length of the pipe to detect any moisture. Dampness in either location is a sure sign of a leak.
Normally, a small amount of water collects inside the P-trap, even when it's not in use, capturing sewer gases that would otherwise sneak up through the drain opening. But if the water in the P-trap dribbles out and leaves the interior of the pipe dry, those gases will escape and linger in the air.
When that happens, it's probably because the washers have corroded and created a small breach. If that's the case, you should be able to replace them and reinforce your work with caulk or plumber's tape to ensure a good seal.
Call in a pro for inspection.
If your drains are clear and your P-trap isn't in need of repair, you'll probably have to hire a plumber.
It could be that there's a broken wax ring where the toilet meets the floor-a situation that you can detect by observing how much water remains in the bowl between uses. If there isn't sufficient water for a flush, you could very well have a leaky seal that has unsettled your commode and let sewer gas seep into the room-both unsanitary and unsafe.
Alternatively, clogged or incorrectly installed vent pipes could be the culprits. These pipes conduct sewer gases out of your home, and fixing them would require specialized equipment and a trip up to the roof. If the vent pipes are involved, tracking down the source of the odor and remedying the problem is a job best left to a professional.