Internal kitchen waste, foul air?

[quasijones]

Hi,

I'm wondering if I have made a c**k up.

As part of an extension/new kitchen I was keen not to have an unsightly kitchen waste pipe on the outside wall.

I installed a 110mm downpipe through the slab to swept bend underneath which connects to the back of a bottle gully on the exterior which in turn feeds to the foul water sewer. The intention was to connect the 40mm waste from sink/washing machine/dishwasher to the downpipe with a rubber adapter.

I was assuming the bottle gully would act as a foul air break but (of course) it does not. Is the rubber seal and trap under the sink going to be enough to stop foul air entering the kitchen? (and will it meet building regs)?

Thanks,

TJ

 

[tony1851]

If you did it the conventional way,and took your sink waste out through the wall and into a nearby S&VP, that would be acceptable (bearing in mind that the S&VP would be connected direct to the drain without a trap).

So what's the difference? You still have your trap under the sink; I don't see why you think you have a problem.

 

[quasijones]

Thanks for the reply Tony. (Just edited this message having re-read your note)

With a connection to a stack, presumably the foul air will vent out of the top rather than up the branches?

I'm feeling paranoid as until I installed the rubber seal onto the internal pipework and there was some pretty nasty niffs!

TJ

 

[Hugh Jaleak]

Perfectly acceptable to connect a waste directly to the drain, without the gulley, provided the correct adaptor is used to make an airtight seal between the waste pipe and the drain and appropriate trap is used on the waste. I would though (personally) upsize to 50mm waste if connecting 3 appliances to the one waste. In the rare event all 3 were to discharge simultaneously, a 40mm waste may struggle, especially after some use and it's partially gunged up with fat/soap/etc....

As a matter of interest, the Osma Bottle Gulley is of a different design, pretty sure using a back inlet connection on one of those would actually give a second water seal in the gulley between the drain and the connected waste.

 

[Nige F]

Hi,


I was assuming the bottle gully would act as a foul air break but (of course) it does not.
TJ

is it missing a black rubber plug about 50mm that is for cleaning access down the drain - seen them with no plug , up come the sewer gasses . Can you post a pic looking down the gulley with the grid removed

 

[Hugh Jaleak]

Reckon he's got the 'other' type of bottle gulley Nige. (Looks like the post has been edited since I commented last night.) Floplast type have a dip tube in the centre of the pot, bottom end of this tube sits below the water line making the seal. Removing the dip tube gives you direct access to the outlet for rodding. Downside is any back inlet connection is also 'behind' the dip tube, so would not benefit from the trapped seal in the base of the pot.

 

[quasijones]

Hugh,

That is exactly what I have, here is the one in question.

http://www.ukhps.co.uk/products/Floplast-Underground-Back-Inlet-Bottle-Gully-Rectangular-Grid.html

Rodding is not an issue - once the 'funnel' is removed the pipework is easily accessible. The base of the funnel does indeed seal to the water stopping air coming out of the grid but there is no water seal to the rear entry point.

TJ

 

[Hugh Jaleak]

As I suspected! The Osma version has a 'hood' over the outlet, with the rubber plug Nige describes, removable for rodding purposes. It is fine though for wastes to be directly connected to the drain provided suitable trap is fitted on the waste.

 

[quasijones]

Gents,

Many thanks for your help and advice. Much appreciated!

Regards

TJ