Right. Plumber neighbour promised to come around to advise but hasn’t done so yet – in fairness he did also say this was his busiest time of year! So will try to sort it myself rather than hassle him further. I’m trying to plumb a sink into my garage – already have water in & waste out (via a standpipe) for washing machine.

Pics attached. Plumber did mention you could get an appliance trap for the sink and connect washing machine waste to that… is this a good idea versus just dropping washing machine waste hose into standpipe as it is currently? (the other clear pipe is drain from dehumidifier)
Can I also just drop sink waste into top of standpipe? (I’d assume not as it’s too high?) Otherwise I’ve got to tee into the existing waste pipe which is lower down… what’s the best/easiest way of doing that?

For the water coming in, there’s just a washing machine hose screwed directly onto the water inlet. I’d like to have a valve to isolate everything, then ideally splits into 3 (ultimately 4 maybe)… the washing machine, something for the cold tap of the sink (possibly at some stage have a feed coming to an instant water heater which will then serve the hot tap), and because this setup is for my home-brewing, something terminating in ½ BSP male that I can connect my existing ball-valve tap & cam-lock onto to provide my brewing/chilling water directly (rather than use an adapter on the sink tap)

The sink unit is freestanding & won’t be bolted to the wall so I guess all the pipes/hoses will need to be flexible so there’s a bit of give for any potential movement!

Bonus points if anyone can give me a list of stuff I can pick up from Screwfix on my way home in half an hour 😃

I’d just stick the washing machine waste into the standpipe as you say. Nothing needed.

Sink waste needs tee’d into the existing horizontal waste pipe. So – one swept tee piece, unsure of diameter from pic.

One sink waste trap required. Again unsure of diameter from pic.

One length of waste pipe to match diameter of sink waste trap. Beware if this diameter is different to the existing waste pipe – you may need reducers somewhere.

Pipe cutter or hacksaw to cut the pipework. Remove the burrs if using a hacksaw.

3 or 4 15mm equal tee pieces for your additional water feeds. Enough valves for each pipe that you want to run. Length of 15mm pipe and a cutter. No idea about your BSP thing.

Hope that makes sense!

TS

Washing machine upstand are 40mm.
No need for appliance trap, what you have is sufficient
Now the sink, 40mm trap to stop the main whiffs coming up
Either solvant weld or compression joints
As for hot water take off you may as well go 15mm barrier pipe from JG. Then buy a few 3 way tee pieces, inserts, blanking caps and push fit to tap flexy hoses from JG

Ta. Largely makes sense 😀
Waste pipe is 40mm, looks like I can get a cheap pipe cutting tool & a push fit tee from Screwfix so that’s all good.
Now, the existing washing machine hose connector is covered in paint… I haven’t tried to remove it, but is there something I can just screw to the top of it if I leave it in place?
I googled and it’s ¾” BSP… could I use this?
https://www.screwfix.com/p/jg-speedfit-plastic-push-fit-straight-tap-connectors-15mm-x-2-pack/85257