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 Common vent for back to back island sinks
Author: rraynoobie (CA)


I was wondering if it is ok to share a common vent with two back to back island sinks. I ask because i am confused about a section of text in the 2016 California plumbing code which states " The island sink drain, upstream of the returned vent, shall serve no other fixtures." Thanks for the info in advance.


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 Re: Common vent for back to back island sinks
Author: hj (AZ)

It means the returned vent has to be the LAST connection to the horizontal drain line.

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 Thanks for the help. :)
Author: rraynoobie (CA)


Thanks for the help.

Edited 1 times.

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 Re: Common vent for back to back island sinks
Author: packy (MA)

I take it to mean no other fixtures can drain into the pipe below the floor. so where the drawing shows an end cleanout, there can not be a washing machine or any other fixture draining there.

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