Chris Johnson
New Member
Hi All,
First time poster here. I have a tight laundry room space and would like to add a utility sink. The washer and existing standpipe as well as the AAV were installed and passed inspection a couple years ago. The drain pipe in the wall drops down vertically. There IS a p-trap for the washer standpipe, you just can't see it in the photo.
I'm contemplating two options:
(A) Leave the existing washer standpipe and trap as is. Give the sink its own p-trap and connect the trap arm to the vertical drain pipe in the wall at a lower point than the washer trap arm. I'd use a San Tee on its back before the wall connection to connect the sink arm to the vent at a point above the sink.
(B) Do exactly what's shown in the IRC diagram below. As such, I would lower and extend the existing washer standpipe/p-trap down several inches and connect my new sink drain to the standpipe ABOVE the existing p-trap with a simple horizontal run. The trap arm would then just connect to the vertical drain line in the wall in the same way it currently does, just lower down.
Option B has less exposed piping but is sure to raise some eyebrows despite being IRC compliant.
Note: I'm in Los Angeles which uses the California Plumbing Code (UPC) and not IRC, however, the CPC does say:
"Each domestic clothes washer and each laundry tub shall be connected to a separate and independent trap, except that a trap serving a laundry tub shall also be permitted to receive the waste from a clothes washer set adjacent to it."
Seems nebulous and open to interpretation to me, but what do I know!
Option A:
Option B:
First time poster here. I have a tight laundry room space and would like to add a utility sink. The washer and existing standpipe as well as the AAV were installed and passed inspection a couple years ago. The drain pipe in the wall drops down vertically. There IS a p-trap for the washer standpipe, you just can't see it in the photo.
I'm contemplating two options:
(A) Leave the existing washer standpipe and trap as is. Give the sink its own p-trap and connect the trap arm to the vertical drain pipe in the wall at a lower point than the washer trap arm. I'd use a San Tee on its back before the wall connection to connect the sink arm to the vent at a point above the sink.
(B) Do exactly what's shown in the IRC diagram below. As such, I would lower and extend the existing washer standpipe/p-trap down several inches and connect my new sink drain to the standpipe ABOVE the existing p-trap with a simple horizontal run. The trap arm would then just connect to the vertical drain line in the wall in the same way it currently does, just lower down.
Option B has less exposed piping but is sure to raise some eyebrows despite being IRC compliant.
Note: I'm in Los Angeles which uses the California Plumbing Code (UPC) and not IRC, however, the CPC does say:
"Each domestic clothes washer and each laundry tub shall be connected to a separate and independent trap, except that a trap serving a laundry tub shall also be permitted to receive the waste from a clothes washer set adjacent to it."
Seems nebulous and open to interpretation to me, but what do I know!
Option A:
Option B:
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