UK Plumber Forum

[joni os]

Location. London Docklands development, 3 storey property ,Soil pipe terminates with Durgo above spill level upper floor.
Soil pipe flows into shared manhole serving multiple properties, Despite rodding of public sewer by utility company this manhole frequently backs up above crown of incoming pipe. When this happens trapped air in soil pipe between manhole and durgo causes problems, slow discharge of WCs and shower waste,
Height of building, dormer windows, vaulted ceiling ,slate roof, together with permits and access for scaffold make extending soil pipe to vent 1 metre above top floor windows a major operation,
With durgo removed WCs flush perfect and power shower fully functional with no backup of water in shower tray,
Replacement durgo experienced identical problems.
Looking for advice,compliant with building control, especially an air admittance valve that could cope with the above conditions

[REDSAW]

cant you try forking it off with another vent? 'y'
i would suspect the durgo is gritting up and sticking. what type is it, as some dont like outside contaminants.
and should not be fitted outside really.

failing that you could always try the 'oh, look. the durgos jammed open and still works' method

[joni os]

failing that you could always try the 'oh, look. the durgos jammed open and still works' method

Householders would be happy if durgo removed, However, their attitude would change should
they return home from a long weekend away, windows closed, and find the top floor bedroom full of sewer gas and associated smell.
If the roof was interlocking tiles I would vent through a tile, but being slate I am reluctant to disturb the existing due to difficulty making good without tingles, especially when working off ladder 10 metres up.
Have also considered connection with strap on boss vented to outside via air brick. If between 1st and 2nd floor, in the event of soil pipe backing up, 1st floor WC should overflow prior to air brick dumping on passerby.
All suggestions are welcome Even the ones that tell me to walk away, which I would do, were this not a longstanding client.

[jonnyswamp]

Get a camera in the offending chamber and see what causes it to back up so often
Could be a fairly straight forward fix external and would save any internal upheavle (can't seem to spell upheavel)