I want to add a dishwasher connection to the cold water supply inlet under sink - what parts and sizes are needed?
Also, the water supply tap is so close to the wall that I can't get a T or Y shaped piece on there. Should I start with an elbow or a stop, and then add a 3 way?
Welcome to the community and thanks for the question. I'm guessing that your dishwasher connection is the standard size which is 3/4 inch (20mm in metric). In that case I would simply replace the current inlet tap you have with this one - Kinetic 15 x 20mm Chrome Plated Double Mini Cistern Stop Tap
This tap has both a 15mm outlet (for the cold water hose for your mixer tap) and a 20mm outlet (for the dishwasher) coming from the one 15mm inlet (as you currently have).
The added bonus is the proximity to the wall will not be an issue when installing this tap.
Remember to turn off the mains water supply before attempting this, and that you will need to remove the cold water mixer hose before removing your current fitting. Then thread tape the water inlet and you can install the new fitting.
Good luck and let us know how you go!
Thank you for joining us. It's great that you've received excellent advice from @tom_builds. The Kinetic 15 x 20mm Chrome Plated Double Mini Cistern Stop Tap is a good option for connecting your dishwasher inlet under your sink. It's a space-saving tap and will not require you to add more fittings to it.
For a superior thread seal, I suggest Kinetic 12mm x 10m Pink Premium Thread Seal Kinetic's heavy-duty thread seal tape has a higher density than standard thread seal tape, which means you need fewer wraps to create a watertight seal. It is suitable for sealing water pipe threads.
It would be great if you could post a photo once you've linked your plumbing together. We look forward to seeing your dishwasher up and running.
If you need more information about your plumbing project, please let us know.