Aab213
New Member
I've read many of the existing posts on this topic, but none are close enough to my setup for me to be confident my plan is correct so I'd like confirmation.
I currently have a single vanity on the second (top) floor draining via a 1.5" pvc into the 3" pvc main stack.
I'm replacing the single with a double vanity. The main stack will be to the right of both sinks and is backset in the wall about 5" (weird but there's a laundry chute to the right of it, so there's more space than normal). On this floor, the stack currently has another 1.5" pvc pipe venting in at ~39" off the ground, also set back ~5" in the wall, which cannot be easily moved.
I believe I need to replace the lower horizontal drain line with 2" pvc that ties into the main stack, add a second tie-in to the main stack right above it for the second sink and then add a vent that comes in above the existing vent since it would be too low if I tied it in below the existing vent tie-in (please confirm).
Please see my plan, above. Summary of my specific questions (but please comment on anything you see that's wrong):
1. Do all the drains/vents need to be 2" or should some be 1.5"?
2. Does the right sink need to drain into the stack directly (as I've drawn) or can it share the lower horizontal drain with the left sink to avoid a third tie-in to the main stack?
3. Will the vent need to tie in above the existing vent tie-in which is 39" (center) above the ground?
In Wisconsin - so WI SPS 380-387 code applies. Thank you!!
I currently have a single vanity on the second (top) floor draining via a 1.5" pvc into the 3" pvc main stack.
I'm replacing the single with a double vanity. The main stack will be to the right of both sinks and is backset in the wall about 5" (weird but there's a laundry chute to the right of it, so there's more space than normal). On this floor, the stack currently has another 1.5" pvc pipe venting in at ~39" off the ground, also set back ~5" in the wall, which cannot be easily moved.
I believe I need to replace the lower horizontal drain line with 2" pvc that ties into the main stack, add a second tie-in to the main stack right above it for the second sink and then add a vent that comes in above the existing vent since it would be too low if I tied it in below the existing vent tie-in (please confirm).
Please see my plan, above. Summary of my specific questions (but please comment on anything you see that's wrong):
1. Do all the drains/vents need to be 2" or should some be 1.5"?
2. Does the right sink need to drain into the stack directly (as I've drawn) or can it share the lower horizontal drain with the left sink to avoid a third tie-in to the main stack?
3. Will the vent need to tie in above the existing vent tie-in which is 39" (center) above the ground?
In Wisconsin - so WI SPS 380-387 code applies. Thank you!!