So what do we mean by undermount sink reveals? A picture best shows this... Below shows you a "positive reveal" and a "negative reveal" around an undermount sink. And yes, there is such a thing as a "zero reveal" where the countertop is flush with edge of the sink. The countertop runs short of the undermount sink flange edge with a positive reveal. The countertop runs past the edge of the undermount flange with a negative reveal. Which reveal is used most often? Probably the "negative reveal". Generally, the positive and negative sink reveals have no up-charge. However, the zero reveal will likely have an up-charge.
Positive Undermount Sink Reveal
So to recap... You have three choices for a reveal for an undermount sink. Positive, negative or zero reveal. Keep in mind, the reveal doesn't have to be 1/8 of an inch... You can specify what that reveal is, but usually doesn't exceed 3/8 of an inch. Best time to talk about this is during the countertop template. If you have more questions, send us a post.
Negative Undermount Sink Reveal