Also called top-mount or drop-in sinks, overmount sinks have a lip that sits above, and covers a small area of, the countertop. They also have both pros and cons. This is an example of an overmount, stainless steel, double bowl sink.
While a top-mount sink sits jovially above the benchtop, an undermount sink is holding on for dear life underneath the countertop.
Topmount stainless steel kitchen sinks, also known as drop-in or self-rimming sinks, are installed over the top of the counter. The sink is suspended by its rim as it is positioned inside a cut out hole of the countertop. For added security, overmount kitchen sinks are clamped into position from below.
Topmount sinks protect the bench top's edges: This is more important on stone bench tops because over time the knocks of pots and pans that happen on the stone bench will eventually weaken the stone and over a decade or so the stone could eventually chip.
Definition of overmount
transitive verb. archaic : to mount over : go higher than : rise above. intransitive verb. obsolete : to mount too high.
Most any sink can be undermounted. Don't make such a project out of it. The main requirement is adequate support. Do what you need to support it so that the top of it is flush or slightly lower than your 3/4" roughtop.
Undermount sinks are bolted to the bottom of a countertop. Drop-in sinks are installed directly through the top of the countertop. Drop-in sinks have a lip framing the sink which, over time, collects dust and residue. This raised lip prevents you from sweeping the countertop debris directly into the sink.
Undermount sinks are defined by the way the sink is installed in relation the kitchen countertop. Rather than being dropped into a pre-cut hole in the countertop, undermount sinks are installed under the counter. Because of the way they are installed, there is no rim between the countertop and sink.
Undermount sinks mount to the bottom of the countertop and are held in place by heavy-duty clips and caulk or a special adhesive. An undermount sink does have a rim, but the rim is not visible because it rests up against the bottom of the counter. The edge of the countertop along the sink cutout is entirely exposed.
Caulking the Gap
If you can reduce the gap to 1/4 inch or less, you'll be able to fill it with acrylic latex or silicone caulk. If the gap is wider, stuff some backer rod in first. This is foam beading that supports the caulk and prevents it from sinking and forming voids.
A flush mount sink, also known as a tiled-edge sink, sits flush with the countertop, supported by the base cabinets. The sink itself will usually have a couple of extra inches around the bowl.
Drop-in sinks represent a sink type that is affordable, flexible, and easy to install. But drop-in sinks do not have much in the way of resale value and are aesthetically outdated.
A common issue with the undermount design is that they can be prone to sagging over time. When the sink starts pulling away from the countertop, leaving a gap, it needs to be hiked back up and secured in place. Undermount sinks work best with solid granite, marble, or concrete counters.
Drop-In Sinks
A drop-in sink is one of the most popular sink types. Also called a top mount sink, it literally drops into a pre-cut hole in the countertop.
Undermount And Drop-in Sink Basin Comparison
Most undermount sinks have a deeper sink basin. The depth of your sink basin is also affected by the thickness of your countertop. If you have a 3cm thick countertop which is 1 1/4 inches you will get that much more depth.
An undermount sink may or may not cost more than a traditional sink. On average, an undermount sink costs about $300.
Simply put, yes, you can replace an undermount sink without having to remove the countertop. After the plumbing and garbage disposal are disconnected, the clips that hold the sink to the countertop from below must be removed. Then, the final step is to break the silicone adhesive bond and pull the sink out.
A dual mount sink has a flat rim that is usually just the thickness of the material, except for Quartz sinks which will have a thicker rim. They can be installed either above as a drop-in or below as an undermount, making it a versatile choice that can be installed in any countertop.
When looking for a sink with good thickness, you need to look at the gauge number. Gauge thickness is a number that refers to how thick the stainless-steel material is that's used in the sink. The numbers usually range from 18 to 23, and basically the lower the number, the thicker the material.
Boos Butcher Block Countertops Can Accommodate Undermount and Farm Style Sinks, but They Require Extra Attention. You should know that Boos recommends against this approach* since it leaves cut edges of the countertop exposed to water, and water can seriously damage wood, as you likely know.
Can you put a drop-in sink on granite? Yes, we can install a drop-in sink on a granite countertop.
Commercial undermount sinks are proven workhorses. These sinks easily mount underneath most counter surfaces and are the logical option for fixtures in hotels, airports, dormitories, restaurants, and public lavatory applications.