I'm having the same mental angst.
Of course if it is all properly installed, there won't be problems, but I am not an optimist. If the seal is done poorly, not only will get mold and may buckle the counter (depending on the material it is made out of...I'm thinking wood at the moment--waterloxed), but smell if there is a tiny leak. Does epoxy/caulk last a good long time? How do you know when it needs re-doing and if so, how expensive will it be.

I know a few people post here that if you do overmount versus undermount, you live in the dark ages, I'm nervous about it and think if it ain't broke, why do the new install.
Just playing devil's advocate here.

I dislike my kitchen undermount sink because there is an uncleanable area at the seam under the counter where bacteria can lurk. I suppose I could spray bleach underneath and try to avoid splashing it all over, but I much prefer a top mount sink for sanitary reasons. In a topmount sink, you have easy access to clean the seam because it is on top of the counter and the crud doesn't hide in the sink. For my new kitchen, I'm considering Blanco's cool new "microedge" sinks that have a sleek minimalist "topmount" option. Even easier to clean are the integral sinks made of Corian- no seams at all (if you like that look).

Chris describes a "negative reveal". A positive reveal shows a bit of sink edge so nothing is hidden. I'd go that route if I were undermounting.

I went for the flush mount. It eliminates the hidden underground for bacteria. My sink is the Ascend granite composite by Swanstone. It can be mounted drop-in, undermount or flush.

Mine both have a zero or flush reveal, so there's no place to collect gunk. No matter how hard I tried, I could never get all the gunk that accumulated under the rim of my old sink. It always creeped me out. Now, not only is there no place that gunk would naturally accumulate, if it does get icky by chance, the area is much more accessible for cleaning.

Just like debsan, we too did FLUSH mount. It doesnt have the drawbacks of either undermount or overmount.

Just have to be extreeeemely precise in installing the counters so that they are flush with the top of the sink. Well our sink is about a 1/32" lower than the counter so that we can wipe water off the counter into the sink.

I just went with an undermount sink, first ever for me. I definitely think it's easier to keep clean and makes it easier to clean the nearby counter - DW just chipped in and agreed.

I don't understand what a flush mount or negative reveal is. Any photos?

Flush mount is exactly what it says. The sink is undermounted, but the counter is cut flush to the edge of the sink. Except for the clear caulk seal, my counter blends into my sink. I'm posting this picture which isn't that great, but hopefully it will give you an idea.

I guess I meant flush mount to mean something different.
What i mean is that the sink is at the same level (and flush) with the countertop. Hence it is neither undermount nor overmount. In addition my sink is counter depth - no need to for the strip of stone in the front or back.

Yes, I always understood flush mount to be what pharoah is showing, and your sink to have a "neutral" reveal, debsan.

Pharaoh,

I love your sink! Very practical but
beautiful too.
What is the granite you used?

Thanks,
~Boxerpups

"Flush mount" is, indeed, what pharoah pictured. "Flush reveal" refers to the amount of reveal on an undermount sink. An undermount sink can have a positive, negative, or flush (neutral, zero) reveal. This refers to how much of the sink rim is exposed or "revealed" in the mounting. With a negative reveal, the counter extends beyond the edge of the sink. With a positive reveal, the sink extends beyond the counter, exposing a portion of the sink's rim. And with a flush or neutral reveal, the counter and sink line up exactly.

Here's an illustration of the difference...

I have a slight positive reveal, and it's the easiest sink to keep clean that I've ever had. Vastly superior to the drop-in style, in my experience.

boxerpups,

The counters are serpentine which is sometimes referred to as marble. This one is connemara from ireland.

My bad. The counterguys called mine flushmount, so I thought that's what it was. Thanks to Holligator for setting us all flush--er a straight.

Love that sink, pharaoh!

Does anyone know if a fire clay or cast iron sink can be flush-mounted? Did anyone install such a sink? Pics, please! TIA!

Holligator, thanks for explaining the reveal differences for undermount sinks.

I have a silgranit sink mounted in Holligator's flush style. Love it, love it, love it! No comparison to a drop-in, IMHO.

Thanks, all. Circuspeanut, I would think that even though the sink has a small positive reveal, the seam where the sink meets the underside meets the counter would still collect gunk. Is that not the case?

Thanks to holligator for the great illustrated explanation of different undermount reveals. I am now reconsidering my topmount choice for the Blanco microedge sink- I hope a good installer will be able to undermount it with a nice "neutral/flush/zero" reveal and eliminate the horizontal gunk space that plagues undermount installations with positive or negative reveals.

But I thought the whole point of getting a microedge was because they can be flush mounted? Otherwise, why not just get a nice undermount instead of spending the extra money?

In case there are any other questions concerning the various reveals for undermount sinks & their pros/cons....see link below.

Here is a link that might be useful: Undermount sink reveals - post pics please!

Writersblock has a great point- I didn't understand what "flushmount" meant with the new Blanco microedge until I just looked at installation instructions. The counter is routered down 2mm to inset the sink edge into the counter, so that there is a nice smooth junction with no bump like a topmount, yet it still has the topmount-like advantage of sliding the colanders, etc. on the stainless rather than the counter surface. Only issue: recommended for solid-surface countertops only! Sadly, since I'm thinking of quartz countertops, this cool flushmount option may not be for me after all. Argh!

Isn't quartz considered a solid surface in that way? I would have thought that in this context solid might mean "same material all the way through" as opposed to something like a laminate where there's a thin layer of something on an underlayment.

pharaoh , I lust for your sink. What is it?

Pharaoh, I too love your sink. Who is it made by?

Clicking on pharaoh's name leads to his/her latest comments being made in 2013.