Soil Stack Ventilation Pipe

[sally123]

Could someone please tell me if it is usual to have a 50mm waste pipe used as a soil stack ventilation pipe. The pipe ventilates a WC bath and sink.
Thank you.

 

[JCSPLUMBING]

It depends on what soil system you got. Usually dictated by the size of the property. You have what sounds like a secondary ventilated system

 

[sally123]

Thank you JCSPLUMBING. The 50mm waste pipe is the only ventilation pipe we have for the system and it is a two story house.
The discharge stack is 100mm but the ventilation pipe (dry part ) is a white 50mm waste pipe.
I can't see another one this small on any other house.

 

[rpm]

Only ever seen 50mm used as a vent on a pumped system.

 

[JCSPLUMBING]

Is it causing you any problems? Siphonage on traps? (gurgling sounds, obnoxious smells etc)

 

[Ch4 plumbing]

Take a look at part H in the gov planning portal, page 11 at the bottom.

 

[AWheating]

min should be 3" (82mm) from memory, builder probably reduced to waste pipe due space available im guessing.