DWV Advice ~ Edmonds, WA

[Vmm_Seattle]

Need DWV advice for two sinks. Main sink will be 16 ft & island sink will be 8 ft from waste stack. Proposed 2 in vent & waste shown in gray. Trying to avoid creating an additional (perhaps un-needed penetration through roof) See yellow.



Essentially asking can we consider the stack extension in a sort of "S" shaped path

 

[Cacher_Chick]

I can't make out your plan very well but if it helps, a dry vent can run horizontally (with pitch) once it reaches a level at least 6" above the flood rim of the highest fixture served by the vent, or 42" above the floor, whichever is higher. It is not permitted to tie a vent into a stack which is the drain for fixtures on floors above. Sometimes it is easier to tie vents together in the attic to share a single vent through the roof.

 

[Sponsor]

 

[Vmm_Seattle]

I can't make out your plan very well but if it helps, a dry vent can run horizontally (with pitch) once it reaches a level at least 6" above the flood rim of the highest fixture served by the vent, or 42" above the floor, whichever is higher. It is not permitted to tie a vent into a stack which is the drain for fixtures on floors above. Sometimes it is easier to tie vents together in the attic to share a single vent through the roof.

Here is a diagram that may help.

It sounds like I cannot tie the vent to the waste because there are drain that occur after it.

Do I have to extend the stack straight up (far left of diagram)?
Can I just extend my vent up to the roof after my sink?

 

[Terry]

The concern would be waste from above, not below.
The island sink would need either an AAV for venting, which is okay in Washington, or a true Island Vent, (which it's not now as drawn)

 

[Vmm_Seattle]

The concern would be waste from above, not below.
The island sink would need either an AAV for venting, which is okay in Washington, or a true Island Vent, (which it's not now as drawn)

Yes, I will use a AAV for the island. So the way I have done it could be an issue even with using a Wye at the island sink attach ? See completion photos . Thanks