I want to move the location for the washer hookup in an older house. At the previous location it was a one and a half inch drain and it worked 'okay'.... I am looking at one and a half inch at the new location but with the drain sneaking around a floor joist. I have attached a picture of the configuration I was thinking of. What are the chances this is going to be a disaster? Maybe I could put a flow restrictor on the washing machine?enter image description here

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    A clothes washer is required to have a 2" drain. Can you add some pictures to your post of the joist cavity where you're routing this drain, and the wall cavity in the laundry room where the wall box or standpipe will go? I think your plan is a little sketchy. Pictures are a good way to get more suggestions on this site. Nov 24 '20 at 13:27

If easy (it may not be since its not new construction), try to do similar to this.

Key features (as required by code):

  • 2" drain
  • Vent nearby to avoid any flow issues
  • P-trap before going into ground to avoid sewer smells

Laundry Drain in new construction


Don't do that: all those bends will cause turbulence, which will cause air blockages.

Go straight down then straight across; this may require making a hole in the joist. There are rules for where you are allowed to cut holes.

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