HI NT

The Natural Philosopher wrote:
Adrian wrote:
HI Folks

Finally traced the source of the nasty 'sewage' smell in our
ground-floor shower room.

It's got one of those nasty 'wet-room' type showers - a 6" tiled
upstand across the width of the room and a 'not-slopey-enough' tiled
area with a shower trap set in the floor.

The water trap is ever so shallow (accessed by removing the grille
over the trap) and, as the shower isn't used all that frequently, and
the water evaporates, the nasty smells from the drain outside find
their way up the waste pipe and into the room. Problem solved at the
moment by stuffing a cork into the drain-pipe - but that's a bit
inconvenient (apparently)

So - what to do about it ?

I've not fitted a shower tray for a while - don;t know what the
current 'traps' look like. Thinking of planting a complete new tray on
top of the 6" upstand to allow a proper trap to be fitted under the
tray and pipe it though a new hole to the drain outside.

Any other possibilities or suggestions please ?

Thanks
Adrian
I have this n occasion. The rather shallow trap gets sucked dry by any
drain activity nearby. An air admittance valve somewhere should help, or
simply tipping a cup of water down the trap every day.

Yes - I guess it might.

Don't know who installed the drainage in this place - but they had one
or two quite 'original' ideas...

The top end of the 4" soil pipe was left open, and vented into the
roofspace of the upstairs bathroom. After a bit of fiddling, there's now
an air-admittance valve on there. That cured some / most of the nasty
smells. When the wind was in a certain direction the draught from the
eaves vents was distributing the smell from the open vent pipe
throughout the house. Nice !

The 'trap' on this shower tray can't be much more than 1/2" of water -
spread over a 3" diameter. Again - when the wind's right (!) the
air-flow through the waste pipe draws foul air in from the outside drain
- which isn't nice. All ground-floor waste pipes simply stop above their
respective drains, without any elbows. Possibly adding elbows to the end
of the waste pipes might help to prevent the air-flow ..?

Don't you love 'finishing off' for builders & plumbers !??

Adrian