Chris247
New Member
Hello everyone,
I am in the construction industry on the commercial HVAC/controls area. I have always done most of my home renovations/additions because I enjoy working with my hands and building things. For my next project I would like to add a washing machine drain and utility sink drain to my basement. The 4" main line is 48" above the basement floor and all the vent stacks are on the opposite side of the house. I would like to use a utility pump for the utility sink. They make a few that do not have a catch basin and the manufacturer specs state that it does not need to be vented. I could just drain the washing machine into the sink, but I would prefer to have the washing machine drain empty directly into the waste line. My thinking on this is so I do not have to deal with straining the washing machine discharge, dealing with the pump getting clogged, and using more electric to run the pump. The utility sink will rarely be used. I am attaching hand sketches of 3 options I thought were possible (sorry my drawing skills are awful):
Option 1: Utility pump and washer drain share a common waste line to the main.
Option 2: Utility pump and washer each have separate waste lines to the main.
Option 3: Washer dumps into utility sink and utility pump is piped into main without a vent.
My question is if these options will work and which is the recommended route to go. My main concerns are if the venting is acceptable on option 1 and 2. The next concern is if option 1 is acceptable is there a chance water from the pump will discharge from the washing machine standpipe and if so would a check valve work?
If anyone can provide any guidance I would greatly appreciate it. Thank you.

I am in the construction industry on the commercial HVAC/controls area. I have always done most of my home renovations/additions because I enjoy working with my hands and building things. For my next project I would like to add a washing machine drain and utility sink drain to my basement. The 4" main line is 48" above the basement floor and all the vent stacks are on the opposite side of the house. I would like to use a utility pump for the utility sink. They make a few that do not have a catch basin and the manufacturer specs state that it does not need to be vented. I could just drain the washing machine into the sink, but I would prefer to have the washing machine drain empty directly into the waste line. My thinking on this is so I do not have to deal with straining the washing machine discharge, dealing with the pump getting clogged, and using more electric to run the pump. The utility sink will rarely be used. I am attaching hand sketches of 3 options I thought were possible (sorry my drawing skills are awful):
Option 1: Utility pump and washer drain share a common waste line to the main.
Option 2: Utility pump and washer each have separate waste lines to the main.
Option 3: Washer dumps into utility sink and utility pump is piped into main without a vent.
My question is if these options will work and which is the recommended route to go. My main concerns are if the venting is acceptable on option 1 and 2. The next concern is if option 1 is acceptable is there a chance water from the pump will discharge from the washing machine standpipe and if so would a check valve work?
If anyone can provide any guidance I would greatly appreciate it. Thank you.


