Why don’t kitchen sinks have overflow holes?
Sinks with overflow holes are not allowed in food preparation areas due to the possibility of providing a place for bacteria and mold to grow around the overflow----stuff you might not want as a condiment for food.
In general, the area around sinks should be kept very well sealed and caulked in order for them to be more easily maintained and kept sanitary. Weather the sinks are self rimming sinks, or under-mount type sinks, the connection between the two should be properly caulked. Of course the Corian type sinks where the sink actually becomes part of the countertop is by far the easiest type to maintain.
Under-mount sinks are very fashionable these days, for a nice “clean” look, yet they can actually be less sanitary than a self-rimming type unless one is very vigilant in cleaning the underside of the countertop where the sink is caulked to the bottom side. Add to this----in the case of granite---that the underside of the overhangs is usually “unfinished” and creates an ideal place for mold and bacteria to grow (kind of like the underside of the toilet tank where there is no enamel coating).
In the following picture you can see where the connection of the sink to the countertop has not been caulked, creating a gap where mold and bacteria WILL grow.
Charles Buell
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Charlie,
I bet you answered a question there, about overflows, that lots of people never thought about.
I find that many people are surprised to find out there is no overflow on kitchen sinks. What I don't like is when there is none on the bathroom sinks-----makes for easy flooding of the bathroom:)
I was considering an undermount sink for my kitchen redo and you just nixed that idea. Maybe my overhang isn't as attractive as it could be, but ummm my health is so much more important than the look of my kitchen... and when I sell it... in the future I may just have a copy of this post on the counter next to the sink.
I knew there was some reason why I shouldn't want those overhang sinks that can only be afforded by the rich and famous!! I do have the Corian type where it is all made together and it cost enough to knock me over. The granite costs even more, I understand.
Barbara and Tammy, I wouldn't want to be accused of spreading visious rumors about about bad an idea undermount sinks are---it is usually only an issue if they are not properly caulked and kept clean----most of the time they are.
Yuck to mold and bacteria in the kitchen sink. But who is Louis....and why is he in the kitchen?
Never mind...just read the title to the post. Maybe I should have done that first, huh? lol
Jim glad you caught that----thought I was going to have send you some coffee or something:)
Yuck, Charles. This goes to show that, just because it's fashionable, doesn't mean it's best. I never thought about having to look underneath the sink to make sure there is no mold growing. I always assumed (you know what they say about "assume", right?) that a sink had to be caulked properly. Now I'll make sure to check all my sinks. Looks like my Sunday's list of things to do is growing.
Hi Heather---better to have the list growing that other stuff growing:)
Charlie - geez, you wear those coveralls ALL the time?
By the way, all kitchen sinks have an overflow -- it's just not a hole. The overflow allows Louis to go exploring!
Did you tell those people to turn up the thermostat on their water heater - 82 degrees isn't hot enough to do anything about Louis, overflow, caulking or not!
Very kindly,
Croakster
Jay, my wife makes me take them off in bed. I know that kitchen sinks have an "overflow" but most people do not like to think of the kitchen floor as an extension of the sink:)
Croakster---you also have an overweight.
Mr Charles,
I believe in coincidences. I think that, at one time, we must have been in the same crawl space.
Your bud, Nutsy at the keyboard
Nutsy I have no doubt that you have left "foreign matter" in every crawl space in the NW.
They need to use nonporous caulk too. I've seen a couple recently that had purchased painters caulk and thought it was the same thing. Great post as usual Charles.
Jack, good point
Never thought to check the caulk or lack of under the sink rim. I will now.
It is easy to overlook---especially if there is a sink full of dishes:)
How big should the gap be between and undermounted sink and the granite coutnertop?
Can I safely caulk this myself or should I get a professional to do this?
Keith, there should not be any gap. While you might make a mess of it, most homeowners should be able to keep these areas well caulked. For best results have a professional do it. They will typically use better caulks that are more difficult for the average homeowner to wrestle with.