Ask the Carpenter: How to remove an old sink without ruining your counter

Q. I hope you can solve my problem with an undermount kitchen sink. When we built our house in 1993, we installed a Kohler Lakefield double-basin cast-iron/enamel sink, which I like very much. Unfortunately, it now has scratches and a couple of small cracks and should probably be replaced. The big problem is that it is under about a ton of granite, which is in great condition and also throughout the entire kitchen.

A couple of years ago, a company attempted a partial resurfacing of the sink, which resulted in a “bathtub ring’’ effect. (They acknowledged that kitchen sinks are difficult to do.) The Lakefield sink has been discontinued, although I did find a couple online quite some time ago. The plumber said he would be willing to give replacing it a try, but no one knows how to get the old sink out from underneath, as it is in sort of a cradle and epoxied to the underside of the granite countertop. I was afraid to buy a new one without figuring out how to remove the old. Any suggestions would be much appreciated.

JEANNE V., Weston

A. Granite countertops can be easily damaged if the sink is not removed properly. Depending on the sink’s installation, you will need to remove caulk, silicone, or epoxy and possibly loosen retaining bolts under the sink.

Some sinks have a shelf or cleat support underneath, but most do not. Either way, the sink needs to be supported while you unbolt it and cut it free. I’ve seen two guys remove undermount sinks with one person holding the sink, while the other one unbolts it and cuts it free. I’ve also seen one guy do this by putting a horizontal board on the counter straddling the sink. He attached a clamp through the drain to the board. The clamp held the sink’s weight, while he removed the silicone adhesive with a utility knife.

I have a specialty caulking blade for my oscillating multi-tool. This blade was originally designed for cutting out windshield urethane adhesive and heavy caulking in commercial applications. This may be the tool accessory needed for your situation.

Ask the Carpenter: How to remove an old sink without ruining your counter

I would call a competent granite company to see whether they can get the sink out after a plumber disconnects and removes all of the plumbing.

Q. One of my basement lally columns, concrete-filled I believe, evidently has had weepy-seepy exterior condensate in the past. A couple of contractors who inspected it have said there is nothing to worry about and to box it if the look bothers me.

After recent rains, though, there was a little water on the basement floor near the column, and I think it’s coming from the base, which looks rusty and flaky. What kind of expert should I call to look at this?


A. Is water coming in from around the column where it enters the concrete floor, or around a metal base plate? Having not seen this, I’m inclined to side with the two contractors who were not concerned with the column after inspecting it.

If you’re still concerned, you could replace the column, but it’s much more difficult to replace a column that has the basement floor poured around it. Finding a contractor to do that may not be easy.

Rob Robillard is a general contractor, carpenter, editor of AConcordCarpenter.com, and principal of a carpentry and renovation business. Send your questions to [email protected] or tweet them to @robertrobillard. Subscribe to our newsletter at pages.email.bostonglobe.com/AddressSignUp.