Sink waste outlet height issue

8 Jun 2013
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United Kingdom
Fitted a new sink but with the new McAlpine Appliance trap (single appliance inlet), the 40mm waste outlet sits about 20mm below the existing pipe outlet through the wall. I don't really want to be drilling another exit through the wall if I can help it.

Does the washing machine connection have to be level with, or above the final 40mm outlet? Can it be lower? I am thinking, add a small extension to raise the 40mm outlet, but this would put it slightly above the washing machine connection point. Presumably ok as the wash machine pipe slopes upwards so shouldn't get waste water draining back into the machine and becoming stagnant.

Could I fit a standard P trap, which appears to have the 40mm outlet at the same height as the sink base and then use a 'self-cutting drain out kit' to attach to the waste on the sink side of the u bend? Again, it would be lower than the 40mm outlet. I guess that I wouldn't want to fit one on the exit side of the u bend as it would pipe up all of the smells from the drain?
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Might be best posting a photo of setup, see if we can see any alternative?
Sponsored Links
Might be best posting a photo of setup, see if we can see any alternative?
I've fitted a standard McAlpine P trap for the time being (at least we can now use the waste. I was afraid of someone pouring water down it and ending up flooding the cupboard below).
I'm going to have to have a think about what I can use to connect the washing machine in. I suspect one of these 'self-cutting' kits mentioned above.
I'll get a picture tomorrow when I'm back at the house.
Thanks so far ;)

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