I hope this hasn't been asked already... I'm installing a utility sink in my garage and I would like to tee it's drain into my washing machine's drainpipe (not sure of the term). The top of the washer's drainpipe is 35" from the floor and has a trap (about 14.5"). if i install a 45 degree wye above the washer's trap (1"-2"), do I need to install another trap for the sink too? Will this setup work? Will this setup cause drainage issues for the washer and/or sink? Am I forgeting anything?

If you don't install a trap you will get the gas smell from the washer line...

i hope this hasn't been asked already........i'm installing a utility sink in my garage and i would like to tee it's drain into my washing machine's drainpipe (not sure of the term). the top of the washer's drainpipe is 35" from the floor and has a trap (about 14.5"). if i install a 45 degree wye above the washer's trap (1"-2"), do i need to install another trap for the sink too? will this setup work? will this setup cause drainage issues for the washer and/or sink? am i forgeting anything?
I hate to rain on Plumbermans parade but he's dead wrong about the trap.
It's against code to double trap fixtures and the washer trap will service both the washer and the sink. The only possible problem that I can see is you may get some suds up in the sink from the elevation of the wye 16 inches or so off the floor )although that's iffy. And if you do a basket strainer can seal off the sink while you're doing the wash. Good luck, Tom

I hate to rain on Plumbermans parade but he's dead wrong about the trap.
It's against code to double trap fixtures and the washer trap will service both the washer and the sink. The only possible problem that I can see is you may get some suds up in the sink from the elevation of the wye 16 inches or so off the floor )although that's iffy. And if you do a basket strainer can seal off the sink while you're doing the wash. Good luck, Tom

If he puts the line in front of the washer trap he WILL get the washer line smell even if it is not what code says

I don't get it. Why should adding a wye above the trap let more smell out than the open washer stand pipe?

if he puts the line in front of the washer trap he WILL get the washer line smell even if it is not what code says

Let's see. He has a trapped stand pipe with a open end. He then adds a wye upstream from the trap on that same stand pipe. Now explain to me how the odor's worse at the wye then it is at the open standpipe since the same trap seal has trapped the sewer gas from both the stand pipe and the wye. Regards, Tom