Washing machine discharge into 3" pipe

[Jona77]

Hi guys,

I am changing some pipes in the basement and at some point I'd like to have a bathroom down there. My washing machine currently discharges into a 1.5" pipe which does a 90 then has a laundry sink drain into it and then heads to the waste stack.

This is the branch line my future toilet/shower will discharge into.

Is there any issues with my laundry machine discharging (after the trap etc) into a 3" pipe? I will likely not do the bathroom for at least 6 months to 1 year. I can't find anything online about it

Thanks

Jon

 

[Terry]

Some places want the washer to have a 2" standpipe and trap discharging into a 3".
The washer can come in downstream of the bathroom.

 

[Sponsor]

 

[Reach4]

Commonly a bathroom is wet vented through the lavatory. This would usually include the toilet being last in line of the bathroom group. Are you proposing that your standpipe drainage enter after the toilet or other bathroom item? I expect that would be fine. If something else, you would have to be concerned that the standpipe could interfere with the bathroom venting.

Codes vary. I am not a plumber.

 

[Jona77]

I haven't really decided the exact location of the bathroom fixtures. At this point it's just the washing machine with a laundry sink on the way to the stack. I was thinking of putting the toilet/sink in the same area that the current sink is. But I can make it work that the washer discharges after all other fixtures without much of an issue if that's the preferred setup. I'm guessing the high pressure discharge can mess with the traps in downstream fixtures?

I will upgrade the standpipe and trap to 2" when I put in the 3" branch.

The washer is currently not vented until it hits the main stack which has fixtures draining above it so it's not really a vent.. I am undecided what I'll do for venting the washer at this point. I have read that AAV's are not ideal for washing machine discharge? At present it doesn't cause any issues with the sink in its current setup so I'm not sure what to do here as well.