Why does a bathroom drain that is not blocked give off a stink?

Our basement bathroom does not have this problem. Only the one on the main floor. The drains seem to be working perfectly. It is something between a dead body smell and a sewer smell.|||Ours is the same way, if you use this bathroom to brush your teeth all the time the paste stays in the drain and then a foul odor after awhile will emitt from it . I pour about 1/2 bottle of clorine bleach into my drain atleast once a month and run hot water into it just open the hot water faucet and let it run a good 5-10 min.|||It's called a "P" trap.|||Sludge does collect in the "trap", that is why it is called a trap, under the sink - usually hair that does not flow through with the water then collects soap scum and, well, the rest of the story you can smell already.


Get some Draino and treat your drains to a good clean out several times a year.|||There could be something in the P-trap(seriously),it's a curved pipe shaped like a P with a drain plug under it.Or...the vent may be clogged,there may be a birds nest in it.|||You didn't say if it was the toilet, the sink or the tub. If it is the tub or sink you may have something in the trap that is small enough to let water through, yet smells. Maybe like old hair bulid up and other stuff. The toilet should not smell, all the water in the bowl is covering the trap.Put some good drain cleaners through the tub and sink drains. If it still smells to it two or three times. they don't sell you the good stuff over the counter.|||Please clean the p-trap and remove the dirts.|||Sounds like someone has used that sink for some number 1s and number 2s. Just let everyone in your family know that they can use the toilet for that kind of thing, and pour some bleach down the drain.|||well if it is coming from your toilet there is a gasket that needs to be replaced it sets under in between the floor and the toilet and you have to remove the whole toilet to get to it, if it is coming from your sink then look under where the drain is and if there is no loop down on the pipes then they were instaled incorrectly|||My bf explained to me that water stays in there all the time so that awful smells from the sewer do not come up from there. What is wrong with your sink? Does it have a design flaw and not have this system? He told me this when he was fixing my sink just as an fyi to me. Are you missing the loop part where the water stays? Look at what people are saying here. They will help you.|||There could be something in the pipe. Pour a little bleach down there to get rid of the smell.|||I had a similar problem...Just pour maybe a gallon or so of very hot water in there maybe it will work for you as well.|||It sounds like water is staiyng in the drain pipe and stagnating..or it could be mildew in your pipes, Bleach is about the only thing that kills the smell....bleach is known to kill some molds and mildew..|||I agree with pouring bleach down sink to get rid of smell;but then to keep smell a way once aweek use 1/2c baking soda and 1/2 c lemon juice or lime juice, wait 5 to minutes for bubbling actions to stop then rinse with cold water, this keeps drain running clear and gives it a lemony or limey smell.|||clean it with bleach and vinegar!


maybe there is something stuck in the trap - you should take that out and clean it, too.|||Make sure the water trap works. The water trap is what keeps a toilet from allowing smells to come back up to your bathroom.|||because it's connect to the sewer system??? Maybe a rat died in there.|||Could be the wax seal under the toilet not making a tight seal, or the sink "P" trap leaking.