There are essentially three different types of sinks, each installed in a different way: top-mount sinks, under-mount sinks, and flush-mount sinks.
Top-Mount Kitchen Sinks: As the most common type of kitchen sink, the top-mount sink is installed by inserting the sink into a pre-cut hole in the countertop. The wide rim around the sink supports it on top of the countertop, and is then caulked in place with silicone for a water-tight fit.
However, top-mount sinks have some functional as well as aesthetic drawbacks. Because the lip of the sink is exposed, it’s not possible to sweep food or liquid directly into the sink, making it harder to clean the edges of the sink and the countertops in general. What’s more, in a tight kitchen, the inch or two that the rim takes up can eat up valuable counter space. Because of these reasons, the top-mount sink is sometimes seen as undesirable and dated, without the clean lines of other sink types.
Under-Mount Kitchen Sinks: As the name implies, under-mount sinks are attached to the underside of a countertop, where special clips ensure the sink stays in place or the sink is supported from underneath by the base cabinet structure.
Under-mount sinks are the answer to just about every negative aspect of the top-mount sink. The seamless transition into the sink makes for easier cleaning and a modern aesthetic, and they take up less counter space than a top-mount sink of the same bowl size.
But under-mount sinks aren’t without their share of negative aspects. They’re typically more expensive than under-mount sinks, and can require a bit of careful design of the mounting system if the sink is particularly heavy.
Flush-Mount Kitchen Sinks (Integrated Sinks): A flush-mount sink is one in which the surface of the countertop flows seamlessly into the sink, with no visible edges or changes in material. This is often achieved with solid surface sinks using Corian bench tops.
The integrated sink shares the same space-saving and easy-to-clean attributes as the under-mount sink, but with the added benefit of a consistent material. While some people like the look of stainless steel, for some, the use of one material is desirable.
Because integrated sinks are custom-order items along with the countertops they are made with, they can’t be purchased off the shelf and are more difficult to find and more expensive.