Nothing interrupts a quiet evening at home quite like the smell of a sewer wafting through the room. But it's not the fault of your bathroom cleaning efforts. Likely sources of the smell include dry drain traps, pooled water and worn sewer trap plugs. Eliminating the smell is usually easy once you find the source. Fixing the problem and opening a few windows will clear the odor and get things back to normal.
Check Your Traps
The plumbing under sinks, bathtubs and toilets all have a u-shaped pipe in them called the trap. The trap has two purposes. One is to collect foreign objects that accidentally fall into the sink. The trap makes it possible to retrieve your wedding ring, for example, if it disappears down the drain and prevents it from traveling farther down the line where it could create a problem. The other purpose of a trap is to hold a small amount of water. This water acts as a barrier between your house and the main sewer line, keeping the smell of the sewer at bay. If you don't use a sink, tub or toilet for an extended period of time, the water in the trap could dry out, allowing sewer gases to enter your home. The solution is to simply flush the unused toilet a few times or run some water in the abandoned tub or sink to refresh the trap. Doing this even twice a month will keep the sewer smell at bay.
Examine Your Main Drain
Somewhere in your house, there is a main drain that leads from your home to the neighborhood sewer system. This drain is often located in the basement. If your home has no basement, the main drain is likely located just outside of your home somewhere between the house and the street. This drain has a cover on it that your plumber opens when he needs to clear clogs and blockages. The drain cover also serves as a barrier that prevents sewer gases from seeping into your home. Over time the drain cover itself may deteriorate and crack, allowing sewer gases to seep into your home. Sometimes the cover itself is intact, but the screw or nut that holds it in place deteriorates. Fortunately, you can purchase a new cover and hardware for around $10 and quickly resolve the problem.
Clean Your Pipes
Sometimes bacteria build up inside pipes and raise a stink. This is particularly true in homes with older cast iron plumbing that has corroded inside, creating lots of nooks and crannies where bacteria can hide. The simplest way to clean the pipes is to periodically pour a household cleaner down the drain. Make sure you choose one that is safe for your plumbing and won't eat into PVC or further corrode cast iron. Allow the cleanser to rest for a few hours before rinsing it away so that it has time to work.
When cleaning your pipes, remember to clean the overflow. In sinks and bathtubs, the overflow sits near the top of the basin. This overflow allows air to enter the system to help with drainage and serves as a drain itself if the sink or tub becomes overly full. Bacteria can build up in the overflow, but people often forget to clean this part of the plumbing system. Because they are elevated, you may need a funnel or turkey baster to get a cleaning solution directly into the overflow.
Include the Kitchen Sink...
When tracking down a sewer smell, check the rubber guard on your garbage disposal. Even if you clean your garbage disposal frequently, the disposal cleaning process usually fails to clean the underside of the guard. To clean it, manually lift the guard flaps up into the sink, turning the guard inside out, and manually scrub the underside of the rubber to remove grime and food debris. The odor that comes from a disposal guard isn't technically from the sewer, but it does accurately mimic a sewer odor and is sometimes the source of smelly problems.
...And the Shower
Take a look at your shower doors. Shower doors are installed on metal tracks that allow them to slide or swing open, depending on the design. During installation, contractors caulk around these metal frames to prevent water from seeping under and around them. When the caulk fails, water becomes trapped in the shower door just as it can around the toilet. To stop the stink, remove the old caulk and then apply a fresh bead of sealant on both the inside and outside of the shower door frame.
Put a Ring on It
Your toilet isn't a single lady, but it still needs a ring. This ring is made of wax and it sits between your toilet and the floor, creating a seal between the toilet and the sewer pipe. The ring helps prevent leaks and, like a drain trap, serves as a barrier between your home and sewer gases. Wax rings become brittle with age and may crack, letting noxious gases into your home. A new wax ring will solve the problem and is fairly easy to install. The project does involve removing your toilet, however, so call a plumber for help if you need it.
Caulk the Can
Your toilet may be the source of your smell even if its wax ring is intact. No matter how well-installed your toilet, it's impossible to mount a toilet perfectly flush to the floor. There is always a gap small enough to allow water to seep under the fixture. When it does, it grows stagnant and plays host to stinky bacteria. To prevent this issue, clean around the base of your toilet thoroughly and then caulk it to create a watertight seal.