Finishing a Wood Kitchen Sink Island Countertop

It's risky, but some finishers say a wood counter with an undermount sink can be finished and perform acceptably. January 14, 2008

I am building a kitchen with an island that is 5'9" x 11'3". The main sink (an undermount) will be in the island and my client desires a cherry wood countertop. The back portion of the island is raised so that the main countertop will be 3'9" x 11'3". If I agree to make the top, how should it be finished? I have done oil/wax finishes on smaller butcher blocks that were designed for chopping, but I know that will not work around the sink. I am leaning toward a WB polyurethane or an oil based marine varnish. With these types of finishes, I would tell them not to use the top as a chopping block. I am very concerned about durability. What would you do?

Forum Responses
(Finishing Forum)
From contributor C:
I'd explain that a wood top is unsuitable for counters with sinks... and that with an undermount sink, the counter edges become part of the sink bowl. This is asking way too much of a wood top which would necessarily have vulnerable end grain on two sides of the sink opening. I have seen this done and I would heartily advise against it!

From the original questioner:
I explained this to my client, but she is insistent. It is unlikely that I will agree to make it. Would anyone recommend a specific finish product? I have seen this done many times.

From contributor P:
A few weeks ago somebody suggested a good way to finish a top like that. You might try searching that topic. I don't like end grain around a sink for all the various reasons. The biggest problem to me is that no matter what you put on it, it's going to end up turning black from all the wear. I've thought that a better solution would be to box it in so that you would have edge grain instead.

From contributor O:
I share your concerns, but I've seen pictures and read accounts of people who've made this sort of thing work. One finish I've often seen recommended is several coats of 100% pure tung oil. This finish is time-consuming to apply because of a very long drying time between coats, but can easily be touched up/repaired by the customer when needed.

I think disclaimers and careful customer education would be important, but this idea isn't so awful that no one should do it. It does require care and a willingness to do periodic maintenance that isn't necessary with other counter materials, and the customer should know, acknowledge, and take responsibility for that.

From contributor E:
This is something that is fairly common and can be done successfully. I used mahogany for my own kitchen with a farmers sink, and although I have had a couple problems with the finish, the end grain around the sink is one area that's still as good as the day I installed it.

I would only recommend a finish I had tried personally and the one I used on mine (Target's CV) I don't feel lives up to its reputation, so I wouldn't recommend it. But there are more durable finishes out there, maybe the Target poly?

From contributor R:
I would go with an exterior 2k poly or epoxy. Both are used in below-the-waterline applications. I would seal (well) the underside of the top as well. Perhaps as important as the finish is the moisture content of the wood when you start. Exaggerated wood movement will be the beginning of finish failure.

From contributor M:
I have built a few counters in wood in the past couple of years, and finished them with Waterlox. It is durable, repairable, and water beads right up on it. Four to five coats makes a very durable finish that looks great. You can easily make repairs later with it if there is a problem.

I have it in my house, and it is just fine on the end grain around the farmers sink. I used jatoba for the wood, and this very hard wood holds up great for a kitchen counter.

As long as the client realizes that there will be some maintenance, there is nothing wrong with a hardwood top. In my opinion, regular cherry may be a little soft of a wood for a kitchen counter, but if the client doesn't mind it getting some dents in it, it should be fine. I used the jatoba as it looks somewhat like traditional cherry, but is so hard it has been impossible for my family to dent so far.