Replies

1. 
   Scott | Jul 07, 2010 09:06pm | #1

   Many bathroom sinks have two bowls, one inside the other, and an overflow drain hole that allows water from the inner bowl to drain into the outer bowl. Do you plug your sink and fill it regularly? If so, sometimes junk can build up in the outer bowl that creates a smell.

1. 
   geoman | Jul 11, 2010 12:56pm | #5

   Thanks Scott

   I fill the sink from time to time for shaving but never all the way up to the drain holes.  Also, the sink is only three years old.

2. 
   DanH | Jul 07, 2010 11:38pm | #2

   It may be that there's a small leak in the drain somewhere.  Especially likely if the drain is old galvanized iron, but it can happen with copper or brand new plastic pipe, if a joint is poorly done or if a nail or screw has penetrated the pipe. 

   First place to look is the horizontal run into the wall -- look for corroded iron or a bad connection of some sort.  (I've seen a couple of situations where the plumber simply forgot to glue the pipe into the tee, and it's held like that for several years with just occasional seepage.)

   You also could have gunk buildup in the overflow and be smelling that.

1. 
   geoman | Jul 11, 2010 12:59pm | #6

   Thanks DanH

   I plan to look very carefully for a hole or leak in the piping.  Since the master bath (where I'm having the problem) shares a wall with the main bath which I gutted and am rebuilding I will be able to give it a close look.  As I told Scott above, this is a fairly recent renovation (2006) so I don't suspect a gunk buildup.

3. 
   cussnu2 | Jul 08, 2010 04:26pm | #3

   single sink or dual sinks in the MB?

   If you have dual sinks, Like mine in the kitchen, you may have crud buildup in the pipe between the two sinks that comes in ABOVE the trap.  I have to take my kitchen sink apart periodically to clean the cross pipe from the second sink.  Some people have luck with baking soda forced into the drain and then pouring vinegar in after which causes the Baking soda to foam up.  Never really works for me because I can never get enough in there to cover the 16" or so tube length.

   As others have said, the overflow is also subject to stinking.  In any case, what you are smelling isn't likely sewer gas.

1. 
   Scott | Jul 08, 2010 07:19pm | #4

   >>>Like mine in the kitchen,

   >>>Like mine in the kitchen, you may have crud buildup in the pipe between the two sinks that comes in ABOVE the trap.

   I knew there was a reason why I plumbed a trap for each bowl in my kitchen....just couldn't think of what it was until you said that.

2. 
   geoman | Jul 11, 2010 01:04pm | #8

   thanks cussnu2

   Single pedestal sink.

4. 
   geoman | Jul 11, 2010 01:03pm | #7

   thanks rdesigns

   I'll check that out first thing in the morning.  It is a rotten egg kind of odor.  However, I do not notice this odor in any other sink location.  Still, I have a private well and it is not chorinated.  Will check back in after further investigation.