Nasty Smells

[Hibou]

On still days and nights when there is little wind, we have a nasty ingress of septic tank smells through sinks and the bath plug holes and and over flow apertures.  I know that the problem is one of  septic tank vapour rising in the soil pipes to exhaust through open plug holes.  This happens when, on still days and nights, there is no wind to drag the vapours up through the stench pipes outlets. I would have thought that the bottle traps and "S" beds would have prevented this, but this is clearly not the case.  My questions are these:  is it possible to buy some form of vapour trap to stop the ingress of  septic tank vapours back up through the stench pipe? If so where can I obtain one? One way to drag smoke up a chimney is to have a spinner in the top of the pot.  Is there something made in the UK/France to encourage the evacuation of smells from the stench pipe working on this principal?  Otherwise, are there any ideas that I have overlooked like somehow adding an extractor to the venting stench pipe system? I Look forward to hearing your ideas.

[powerdesal]

We had exactly the same problem from our shower drain, I suspect it does not have a water filled trap. Solved the problem by always leaving the plug in when not actually in use. Other than that, no ideas.

[JMB]

If you paint the vent stack matt black it may create an updraught within the pipe when the sun shines on it. 

[Cat]

There is an article here explaning why water traps may not always trap nasty pongs http://www.frenchentree.com/living-in-france/DisplayArticle.asp?ID=29492 

 

[JMB]

Now that is a very informative article - whatever did we do before the Internet?!

[Pads]

We asked our Dads !![:D]

[JMB]

LOL

[Cat]

We had a similar problem, whiffy niffs oozing from plugholes and overflows.  It was partly due to syphoning of the traps when the dishwasher or washing machine pumped out to empty.  Mr Cat put in a couple of little anti-syphon vents further along the system and that sorted that.  The other cause was gradual drying out of the traps in the 2nd bathroom (which hardly ever gets used).  We deal with this by running the taps and flushing the loo every few weeks to replenish the water in the traps.