Actual Size of Undermount Sinks

Undermount sinks are installed below the counter.

Choosing the right undermount sink isn't hard if you follow a few rules. Undermount means just what it says: the sink is mounted under the counter top instead of featuring a lip that overlaps the hole in the counter top. If you are replacing an existing sink, it is important to measure correctly. Undermount sinks are found in kitchen and bathroom models.

Openings

Determining the size of the replacement (or new) sink depends upon the size of the opening in the counter top. Unlike topmount sinks, there is no lip to cover irregularities or slight gaps in the opening. Most contractors adhere to standard sizes, but sometimes in remodels, the opening might not be standard. Possible reasons are that the house is old and products have changed over the years or it was a custom sink.

Installation

Install undermount sinks one of three ways. Each method requires a slightly different opening size. A positive reveal means the counter top does not come flush with the edge of the sink. The opening is about 1/8-inch away from the edge, exposing a little of the sink rim. A zero reveal is ideal if the sink opening exactly matches the counter top opening. The sink bowl edge is flush with the opening greatly reducing the possibility of grime accumulating around the edge. With a negative reveal installation, the sink is a little large for the opening so the edge of the counter top extends over some of the sink bowl.

Standard Sizes

Select standard kitchen sinks from single bowls 22 inches deep by 24 inches wide, double bowls 22 inches deep by 30 inches wide and oversize, sometimes with three bowls, at 22 inches deep by 36 inches wide. Standard depths are 8 inches. Consult with your home improvement store or plumber, if in doubt. Available counter space for sink length and width and undercounter clearance for deeper sink bowls are important factors. Bathroom sinks come in a variety of sizes and shapes so there really is no standard. Counter top or available space and clearance is a huge factor. Of prime importance is selecting a model specifically for undercounter installation. Know if you will need a positive reveal, negative reveal or zero reveal.

Counter Top Types

Choose undermount sinks for granite, solid surface materials such as Corian, ceramic tile and marble. Undermount sinks are not as compatible with laminates because of the unfinished edge of the opening. Besides its sleek appearance, installing an undermount sink has the advantage of wiping spills or crumbs directly into the bowl.

References

• Determining Sink Hole Size
• Choosing Your Kitchen Sink
• Kitchen Sink Sizes