soil/drains banging

[sarahproperty]

we have a ground floor toilet. the drain runs to a short (about 1 metre high) indoor soil stack which has a grey lid on it, but its not like a normal soil high soil stack as there is no ventilation at the top/no smells come out of the top.

this runs outside where there is a junction. a bathroom and proper tall soil stack at the back of the house runs into this junction and then the pipes all lead around the front of the house (where there is another proper tall soil stack).

recently, when flushing the downstairs toilet, the 1 metre high indoor stack and/or pipes make a banging noise and appear to shake.

we have tried putting costic into that toilet bowl in case it is a blockage.

can anyone advise what might be wrong? we recently had our drive way laid and the pipes were therefore re done. could this have anything to do with it?

thanks

 

[Softus]

can anyone advise what might be wrong?

Might be a sticking Durgo (aka AAV).

we recently had our drive way laid and the pipes were therefore re done. could this have anything to do with it?

Could what? What pipes were "re done"?

 

[sarahproperty]

thanks softus,

the underground pipes from the back of the house (inc soil) were relaid so that they are now attached to the junction which the 1 metre high inside soilt "stack?" (i think this is the durgo?) also goes into.

so i think the 1 metre high stack is a "durgo". what do you mean by it sounds like it is "sticking?

since the pipes were re-routed, the rear upstairs toilet and bathroom (which has its own vented soil stack over there) now leads into the junction with this durgo (which is further down the slope/run). then the run from that junction (where the durog is) leads into another drain and vented soil stack at the front before it hits the main sewer.

could the fact that my rear upstairs bathroom is higher than the top level of the ground floor durgo be an issue?