Plumbing guys: Washer draining directly to waste line

[iamwiz82]

What are the requirements? I'd like to keep the laundry sink, but not have it dump directly into it. I've been told that a 3" waste line is necessary, which is what I have, but is it ok to have both the sink and washer drain into the same 3"?

 

[FoBoT]

you need a Y loop thingy, trap something, lets google

 

[NoShangriLa]

Yes, it is okay to have laundry sink (3 fixture units) and washing machine (3 fixture units) on the same trap arm, but your trap arm must be 2" pipe with a max total length of 8' from stack.

1 1/2" pipe -- 2 fixture units.

2" pipe -- 9 fixture units.

[add]

you need a Y loop thingy, trap something, lets google

Do you mean a tee for the 2 fixtures to connect to the same trap arm, or a Wye (y) for drainage, or 2 P-traps for the fixture seals?

Put a standpipe off the trap for the washer.

That is how one would do it, however the trap arm must be 2" & the base of the standpipe must have a P-trap. Standpipe length depends on each region local plumbing code.

 

[0]

Put a standpipe off the trap for the washer.

 

[JC]

The standpipe must be 36" high, or above the highest level of the water, so it will not siphon out.

 

[db]

Standpipe receptor: max. 30", min 18" above trap weir.
UPC 804.1
CABO 3701.6.4