Heres a picture labeling what each pipe is .. just wanna see if you can tell me the easiest way to run a drain for the washer hook up .. or do i have to run it to the main stack
Drop down a floor and tie in below the p-trap of the tub. Not on the tub drain, below it on the next floor down,.
It will need it's own vent which can tie in at 42" above the floor.