Cast soil pipe problem?

[H0pp0]

We recently had our gutters & facia boards, etc... replaced by a company and they've cut down the cast iron soil pipe to just underneath the roof line, rather than cut the boards to fit around it and have it poking through the roof like it used to.

They talked of fitting an air admittance valve but now reckon because of the difference in diameters between cast and plastic pipes that it wouldn't fit and have left it open.
Occasionally we now get smells from this in my sons bedroom next to the bathroom.

I've seen you can now get an external air admittance valve but not sure that would be a suitable diameter to fit to a cast pipe?

Hoping someone can help me fix this?

 

[nortonj]

Surely its the company's responsibility to sort this?
However you can buy a cast to plastic adaptor, try drain centre, they will have what you need, but measure the cast stack first.

 

[H0pp0]

Thanks for the reply.

I know, but they don't seem to be very adept at plumbing matters.
Will measure the cast pipe diameters when I can get the ladders out, just thought i'd ask the experts here in case I was looking at this all wrong.

 

[nortonj]

The fitting i have used in the past fits internally inside the cast, then has a socket on the otger end, so u will need a small length of plastic pipe for the air admittance to fit on to.

 

[H0pp0]

I was looking at one of these:

www.ebay.co.uk/itm/FloPlast-AX110-External-Air-Admittance-Valve-Durgo-To-Suit-82mm-110mm-BLACK-/122011155115?hash=item1c686e7aab:g:wrIAAOSwPcVVpkho

But without measuring the pipes I/D I was unsure.

That looks like it would do the job. Any idea's what it's called or where I could get one from?

 

[Madrab]

I don't understand why 2 135Deg bends and a bit of pipe couldn't have been used and run it up over the gutter level as usual? Jeesh, they could even have just used a fernco to connect it. Do remember that an external AAV should really be inspected annually.

I'd be getting them back to fix it, as it currently contravenes building regs.

 

[H0pp0]

I know, all the new builds going up round here are like that. (Been driving round looking at pipes - sad or what?!).
It's probably the clip holding the pipe to the wall just below the roof line gave a nice place to cut the pipe.

 

[Madrab]

Never good. If it's been cut and the pipe and opening is anywhere within a few meters from an open window, then it can't be left like that. Time to get them back and quote, If I remember correctly, Part H of the Building Regs to them.

 

[Steelmasons]

Soil and vent stack will require an open vent pipe in order to relieve any positive/negative pressure fluctuations @ manhole....an AAV should never be used on a soil and vent stack installed @ head of drain.....you may find a relief vent somewhere near manhole although possibly non functional.
Industry gone to the dogs..

 

[Nige F]

Stuff a flexi in it and loop it over the gutter

 

[AGAS]

(Been driving round looking at pipes - sad or what?!).

 

[Hugh Jaleak]

Please do not alter it, an open vent is provided for a reason. Part of my job involves cleaning sewers with high pressure water, and we are increasing finding we are getting 'blowbacks', caused by pressure fluctuations in the drain being unable to escape.

I think on almost every occasion, the problem has been investigated and found to be caused by alterations to the house drain system, where open vents have been removed in favour of AAV's and either heavy objects placed on manhole covers, or covers completely buried.

Open vents provide an essential escape for positive pressures in the drainage system, ultimately your fascia company either needs to come and reinstate the pipework correctly, or if they are unable or unwilling to do so, get the work done by a third party and reclaim your costs from the fascia company afterwards.