External Air Admittance and Waste Pipe Design

Here you go. Also some info on the Floplast AAV.

dormer balcony.jpg
Floplast AAV.jpg
 
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Is there an open vent elsewhere on the stack, or the system within the property? People tend to use AAV's for ease of installation/cost savings etc, but drains should be vented, especially at the head of the run. Ideally needs to be vented, otherwise you could have problems, and it doesn't look the easiest of places to retrofit a vent arrangement at a later date....

We seem to be coming across more and more problem during the course of my work these days cleaning sewers, where vents have been swapped for AAV's and then we blow toilets as the pressure from the jetter cannot escape.
 
That makes sense on the inlet. I’ll continue it up over the roof line and put a standard vent on it. Will probably work out cheaper but was going for a cleaner look with the AAV.

There was no other vent which seemed to have no impact on toilet flushing. When I took out the cast iron stack to put in a rest elbow it was blocked with cast iron flakes and mud. Dry at the top, moist at the bottom but blocked for a good 600mm for the last few decades at a guess.

The toilet waste will be in the corner where the coping is. The Ø110 pipe will come out with the bottom of the diameter on the edging strip at the bottom of the cream render – quite low to the roof tiles, especially taking the fall into account.
 
My concern would be, with an AAV, if flushing the top WC would cause problems in lower appliances, as well as the aforementioned issues with blocked pipework. Looking at the height involved, I suspect it wont be the easiest of places to get to, and you might be cursing if you've got to get back up there at a later date to alter the pipework....
 
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I obviously just did :LOL::p
Would you mind explaining the reason why???..:censored:
..possibly self/induced syphonage????

In this setup, basin trap could be pulled and also, depending on reducer/boss used, the basin waste can drop down into the 4" branch and create a nice toilet roll and sh#tcatcher! Just what happened at my sisters house last Christmas when we all went round for din-dins... Guess what my job was that day :eek:
That is why you have an AAV to stop self siphonage and you could also uncap it and stick your hands through to clean any ****e catcher!:p
 
Affluent streets..especially Daneland..;)
Churchill Road looking over Oak Hill Park....beautiful weeping willows around the brook..often walk the dog over there.
 
I obviously just did :LOL::p
Would you mind explaining the reason why???..:censored:
..possibly self/induced syphonage????

In this setup, basin trap could be pulled and also, depending on reducer/boss used, the basin waste can drop down into the 4" branch and create a nice toilet roll and sh#tcatcher! Just what happened at my sisters house last Christmas when we all went round for din-dins... Guess what my job was that day :eek:
That is why you have an AAV to stop self siphonage and you could also uncap it and stick your hands through to clean any ****e catcher!:p

No! Not when AAV is downstream.
 
Affluent streets..especially Daneland..;)
Churchill Road looking over Oak Hill Park....beautiful weeping willows around the brook..often walk the dog over there.

A toboggan Mecca when we have a decent snowfall!

You must know Dodgy Dave!?
 
Oakwood Plant Group/demolition?
Do you know Mr Lennon? :)

Cheshunt rugby club? You go there at all?
 

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