Kitchen drain pipes - Advice needed...

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Hi guys,
I'm in the progress of re-doing my kitchen, but will soon need to do the waste pipes and could do with some advice.
I've stuck a quick pic (its crap..I know) which will hopefully make what Im saying clearer.
drainsjj2.png

I had planned on the pipes being in a sort of 'T' shape with the Sink trap (with dishwasher feeding onto one of the Spigot pipes) on the right side of the 'T', the Washing machine using a standpipe arrangement being on the 'Upright' part of the 'T', and the left part of the 'T' goes through the wall out to a hopper on a drainpipe (we're in first floor flat).
Still with me???
I was going to ask what sort of 'fall' I should have on the pipes, the Sink branch being appx 80-90cm long to the t-piece, and the Wash machine branch being appx 50cm long. But then I realised that the sink trap would be about 60cm from floor level, but washing machine trap - due to standpipe arrangement would be much lower... :confused:
Would it still be poss to join the two branches at a t-piece and run one waste through the wall - even though the sink branch would have something like a 30deg fall on it, to the t-piece?? Or am I likely to have to drill two separte exits for the Sink + washing machine drains??
Obviously I'd prefer not to have to do the latter cos
1) It'll take ages to drill two holes with the core drill
2) I think it looks ugly when there are pipes coming out of the wall outside... :(

Any help greatly accepted, O wise ones :D
 
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There's nothing wrong with running a sink waste at a 30° fall.

Clearly you wouldn't have the room to do it for much more than a short stretch, but it sounds like you're doing it merely to facilitate merging with the waste from an appliance, so that's just fine and dandy.
 
You WILL get gurgling though with too steep a fall. Consider coming down from the sink then going across.

The washing machine waste could always be extended and tee'd into the main run from the sink.
 
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Hi guys,
Thanks for the replies, I had a quick look at the setup last night, it doesn't seem as tho the 'drop' from the sink branch will need to be as steep as I thought. :)

I'm able to lift the W/M standpipe up higher than I had thought whilst still keeping a decent height on both the standpipe + keeping trap at reasonable level.

I was thinking then that I might want to put vertical vent pipes rising from each branch and joining into a AAV, to help prevent suction when one of the branches has flow in it. :rolleyes:

But i've decided I'm probably WAY overcomplicating things :oops: , since the runs are so short each side of the branch, and the pipe on the outside wall wont be too long, prob about 1.2m dropping into a hopper. Which I'm then hoping - cos its open to air (as all drains are I suppose) will allow air back up pipe to break suction.

So I'm just gonna keep it simple and hope it all works ok - if it don't i'll be stuffed since it'll be behind kitchen cabinets. :confused:

Thanks Again ;)
 

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