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Overflow on Vanity Sink


Platinum Member
Oct 19, 2009
This is the first time I've ran across this and it got me to thinking. Performed a final plumbing inspection on a new residence today. Went into the hall bath, turned on the hot water, pulled the stopper to fill the bowl. I always do that so that I have a volume of water to check for leaks underneath.

I'm letting the water run... checking other stuff... look back and the sink is about to run over. WHOAAAA NELLY!!! I thought all vanity sinks had overflows.......

I'm thinking... is this a code violation??? Then I walk through and see the kitchen sink.... well golllly dern.. the kitchen sink don't have one..... I knew that but it seems to me all vanity sinks have overflows...... I'm digging in the code but I'll post here.. you guys are smarter.....
I've alway figured it was a feature to prevent the kids (and absent-minded adults) from overflowing the sinks and tubs, not a code requirement though.
Overflows are not required by code, however if they are intalled then it needs to drain on the house side of the trap. When I was plumbing full time I found lots sinks that did not come with overflows more so in the more exspensive sinks.

have a wonderful 4th and don't do anything I wouldn't do which keeps it pretty wide open. :)
Thanks for the replies. It was one of those hmmmmmmm moments!
I saw a sink at the home improvement store the other day without an overflow drain, the sink was made flat with a v-shape that drains to the sink drain, cool..... I figured the faucet can only put out so much water and there was no drain stop to fill the sink. Could be wrong in my thinkn'

The one i was inquiring about had a pull stopper in the faucet assembly. That's what started me thinking.......... Don't know why I noticed there wasn't an overflow!
Air gap between spout and flood level rim is required, but no overflow drain, especially noticeable on some of these ridiculous new-fangled blown glass and ceramic pedestals that some think are so cool.