Plumber: Weighing options for new kitchen sink

Q: I am planning to remodel my kitchen. The project will include installing granite countertops with an undermounted kitchen sink. My first choice for the sink is cast iron, but I'm told that the weight can make undermounting an issue and it may not be possible. Is there any way I can have an undermounted cast-iron kitchen sink? Do they even make them? Also, what about the finish on cast iron? We don't want to trap the sink under a counter and have the sink finish look dull after a few years. — Rich, Kansas

A: My last column on kitchen sinks must have struck a chord, since I have received a lot of letters asking about them. Cast iron has made a big comeback over the last few years and is a hot product for many plumbing-fixture choices. Mostly because the word is out that most cast-iron plumbing fixtures are made with over 90 percent recycled and reclaimed materials. Many contractors who are building green have switched to cast-iron plumbing products whenever possible.

Cast iron is a tested and accepted product that has been around as long as I can remember, and I'm over 50 years old. Plumbing manufacturers have jumped at the chance to join this cast-iron resurgence and have recently added many new colors, styles and finishes to their lineups.

With all that in mind, I can say with certainty that you have been given some misguided information when it comes to undermounted cast-iron sinks. Yes, they make them. And yes, they can be installed under granite countertops.

Basically, an undermounted sink has to be special ordered for the job. Undermounted sinks have thinner flat flanges for the edges that sit flush with the underside of the countertop. Cast iron is a heavy product, so the contractor usually builds in support brackets and/or special framing to carry the extra weight load in supporting the sink, so it may be a little more of an investment to install a cast-iron sink, and the materials can be more expensive than other sink choices. But it certainly can be done if you can afford the extra costs.

Once installed and undermounted, a cast-iron sink can give a striking appearance with its vivid color and bright finish. A high-end cast-iron sink can look beautiful for decades, and many manufacturers give very long warranties against chipping, scratching or burning of the surface.