I'm installing a dishwasher in my flat and the water intake under my sink are 2x 1/8" (hot and cold) with no extra output for a dishwasher like you see in newer houses.
I need something that will take this 1/8" hot water line and split it into 3/4" for the dishwasher intake and still keep one side 1/8" for the sink. I tried looking in my local hardware store, but could not find something like this. If both sides would have a shutoff valve that would be great too.
I was recommended to take off the current 1/8" connector to expose the bigger pipe behind, but for this I need to turn off the main water supply for the flat which I do not have access to. It's an older building with a landlord which never responds to messages, so it's not really an option to do this unfortunately.
I've attached a picture of the wall and a drawing with my awesome paint skills of what it looks like.
Any suggestions would be super appreciated!