I have one of those deep plastic wash basins/laundry tubs that you see in laundry rooms most of the time that I want to install in my garage. The wall I plan to place it next to has a 4" PVC waste drain pipe behind it. That pipe handles the waste from the master water closet, tub, shower, etc and I think for the washing machine all of which are above the garage. My question is, by code (Fulton County/Atlanta, GA), can I tap into that waste drain pipe or do I need to provide a seperate drain for that tub? The waste pipe goes into a septic system. Can I just make the tub drain straight to the outside of my house? My overflow pan under the washing machine currently does this? All I am planning to use the tub for is washing hands, tools, etc after working outside in the yard. If I drained it outside, it would go onto my driveway and drain away to the yard. I might also use the tub to wash water based paint off brushes and such. I don't know what else, but nothing that would do damage to the yard. Probably draining to the septic would be better, but I don't know about the code for tying into the existing waste drain.