Plumbing - can anyone identify what this is?

[The Natural Philosopher]

I am not sure that is the case. As far as I can recalll you merely need one open pipe per 50 meters or something of drain, to vent positive pressure.

Air valves can be then added wherever neded to prevent siphoning.

Well my parents house in 1953 had exactly that arrangement.

BCO's can be surprisingly ignorant.

Mine was not aware that

- if you use guttering you must comply, but there is no requirement to use guttering at all! Merely that there mus be wome means of stopping water getting onto your walls..

- you don't need safety glass in a multi-paned French window (leaded) and indeed, it can't be realistically cut that small either.

In every case the regulations section begins with a 'statement of objective'. Whilst suggested methods of achieving those are outlined, often in detail, in the final analysis, you can appeal to the spirit of the regulations. It is up to you to demonstrate that your solution achieves the OBJECTIVES.

In the case of drains, these are a sufficient flow rate to keep them running freely, a provision to prevent build up of noxious and combustible gases, and a provision to prevent these gases from appearing inside the dwelling.

Any combination of slopes and pipe diameters and vents and u-bends and traps and durgo valves that achieves this 'meets the regulations'

[Ed Sirett]

It's not about separation of the drainage but making sure that grey water goes directly to below the gully cover and not via hoppers, downpipes, shoes and the gulley grating.

As I said 50% of buildings must be non-compliant.

She probably does (in regard to both verbs).

[Ed Sirett]

That's a most useful commentary on the regs. Thanks.

[Doctor Drivel]

The AAV is too low it must be above the highest point were water drains from. It needs to be extended, or on each sanitary appliance fit a dry HepVO trap, which are AAVs in themselves.

[Doctor Drivel]

Cap it off using an inspection cap, so the drain can be cleaned. Then fit a HepVo trap on the sink.

[Doctor Drivel]

It is too low.

[Doctor Drivel]

Learn about HepVo traps.

[Doctor Drivel]

Must be open vented and every 5th house vented too.

[Tony Bryer]

No, pre-war I am fairly sure that the byelaws prohibited single stack drainage, basins, baths and sinks being required to discharge via a gulley. From 1965 the [then] new Building Regulations required all waste pipework to be inside, effectively requiring single stack drainage.

[Heliotrope Smith]

Bad advice to cap off. Think before giving advice, could cause more problems. Probably comes up in 4" for a reason. Could be a tee off from a toilet waste for instance.

[Doctor Drivel]

I was under the impression that all that was on the stack was the kitchen sink.