Bottle gully to 40mm waste

29 Nov 2019
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United Kingdom
Sounds like a silly question, but what's the best way of connecting 40mm waste pipe to a 110mm knockout on a bottle gully.


Knockout seems a little shallow for something like this

Is that the best method?
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If it was me I'd use a single waste adapter/connector

edited due to the pic being lost
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Solvent weld then?

The connection isn't long enough for anything else really.

The trouble with boss connections is that most, if not all, manufacturers use different fittings/methods - they aren't universal.
If you haven't already got the gulley, then get the Screwfix version with 110mm socket on the back inlet, fit a waste adaptor into that, and connect your waste. Otherwise glue the waste adaptor into the knockout then connect your waste.
Waste pipe adaptor. .jpg
Thanks for the replies. Wavin (Osma) are saying you can't use waste pipe underground. Which is interesting as some images show the osma 4d900 gully with a waste pipe size knockout.

This is for sink and dishwasher 40mm waste exiting through the wall and dropping into the side of the bottle gully which isn't very deep. I guess this is only to do with blockages? Was trying to avoid going into the top grill.
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