adding outdoor sink, drain to cleanout plug, and venting?

Question

I hope I describe this properly. Out in my back patio, there's an outdoor faucet/hose connection and a cleanout plug coming out of the stucco right next to it. I want to add an outdoor sink/tub for dirty cleanups without having to reenter the house. I can tap into the garden faucet and run cold water fairly easily. My question is whether I can open the cleanout plug and run the drain pipe into a T attached to it? If so, do I need to run a vent pipe up above the roofline? Also, where do I connect this vertical vent pipe (between the trap and the cleanout T plug)?

Answer 1

I would use an Air Admittance Valve for the vent. You can purchase these at Home Centers. Behind the sinks trap, install a tee looking upwards. Cut a piece of pipe long enough to go as high as possible with the AAV on top of it. AAV's are normally used on island sinks where a vent pipe going upwards is not possible.

Answer 2

Outdoor Sink Drain

Answer 3

You can use the clean out for a drain, but use a Y instead of a T. You want your drain to slope and use the end of the Y as a clean out. You don't have to run a vent pipe above the roof, but the drain should be and if by code must be vented within 18 inches of the sink drain. They make vents with check valves in them that you only need to run a short upright for. Like six inches or so.