Question: What's That Smell?

WHAT'S THAT SMELL?

I knew you'd look.  No, no gross pictures, just a discussion.  Have you ever been in a home or building and detected an "odd" smell that seems to be coming from a bathroom?  And no one has been in that bathroom for a long time, like weeks.  Sometimes it smells like sewage.  What can be causing that smell?  

Answer, it could be the trap.  The trap is the part of the drain system that has a U or J shaped bend in it.  A plumbing trap is not there to "trap" your wedding ring, earring, or other small item you may drop down the drain accidentally.  The trap is there to prevent fumes from backing up into the building from the sewage system.  Some of these gases can not only smell bad but may also contain toxic fumes.

The photo on the left, courtesy of Code Check, shows a U shaped trap with a supply of water inside the U.  You can see that as long as the water is in the trap gases will not be able to move from the sewage system back into the building.   However, if the water is not there, gases can easily follow the path of least resistance and enter the building.  So, if no one has used the bathroom device (sink, toilet or shower) for a while, it is possible the water that was in the trap has evaporated and the trap is allowing the gases to pass. 

So what's the fix?  If you have a bathroom that does not get much use, such as a guest bathroom, simply periodically run some water into the suspect device to refill the trap.  If you did this once a month it should take care of the smell. 

                                   Richard

Comments in this blog posting are the intellectual property of Richard Acree, President, HABITEC Home and Building Inspections, LLC, and contributing members of the Active Rain Real Estate network, and are intended to educate and otherwise assist home owners, sellers and buyers, building owners, sellers and buyers, realtors, real estate investors, property managers, and lenders in the process of owning, buying or selling homes or commercial buildings.  HABITEC is a residential (home) and commercial building inspection company serving Middle Tennessee including Nashville, Brentwood, Franklin, Murfreesboro, Smyrna, Mt. Juliet, Hendersonville, Dickson, Belle Meade, Columbia, Spring Hill and more!  In addition to building inspections HABITEC offers Environmental Services for mold assessments, radon testing and water quality analysis.  Additional information about HABITEC can be found on our website at www.habitecinspections.com, or call 615-376-2753.