View Full Version : Basement Washing Machine Drain

11-20-2008, 07:40 AM
What line is safe for a washing machine to drain into? In my basement remodel my wife and I talked about possibly moving the laudry to the basement. I thought if nothing else I could at least get the power and water setup for us or the next guy.

I have a 3/4 bath in the basement already right beside what will be the unfinished furnace/laundry room. So supply and drain are close. The basement bath has its own vent (1 1/2"?), though I assume it gets connected back to a main vent in the attic.

Can I just waste into the shower vent for my washing machine?


Gary Swart
11-20-2008, 09:38 AM
I'll leave the evaluation of the entire plan to the pros, but I can tell you that your washer must have a 2" trapped and vent drain. I think you could share the vent as a vent but not as a waste.

11-20-2008, 09:47 AM
You can not waste over into the shower vent for the washing machine drain.
The washer would siphon the trap of the shower dry in seconds.

The santee on it's side for the shower needs to be replaced with a wye.
The vent needs to have a wye fitting also.

If you want to add a washer, add another wye before the shower vent, and come up alongside of it.
Add a santee on the vertical about 12" above the floor, and use a 2" p-trap with a 30" standpipe.

The two 1.5" vents can then tie together at 6" above the standpipe for the washer.