I find it funny that people say this all the time, and yet if you go to Europe, every last kitchen has this set-up and some of them are decades old. Yes, you'll get weathering of the wood, even if it's well sealed, and it needs to be done properly. Yes, it might invalidate the Boos warranty, but how often do they even get a warranty claim? I doubt it's often. The stuff is pretty hard and stable.

I wished I thought to ask about this earlier... before we started the renovation. I wanted a butcher block next to my stove top but decided not to go with it because of the prep-sink in that counter. Since then, I've seen so many pictures of undermount sink in butcherblock countertop in magazines!

I'm not talking from experience but I wonder if the sealants are good enough now so that it wouldn't be an issue.

I tried unsuccessfully to talk my GC into undermounting my prep sink in my butcherblock island (from Grothouse Lumber). He just wouldn't do it - he said the edges wouldn't seal properly. I showed him pictures in the magazines, but he said no. I adore him, so I went with his suggestion of routing it into the countertop, which you obviously couldn't do with a farm sink. There are obviously ways to do this, and I kind of wish I'd pushed harder. I think you could do it - just seal the edges often. You couldn't have an oiled finish - it would have to be a poly. My finish is oiled, so I guess that's why it wouldn't have worked - the edges would have looked different.

If you want to see mine, it's in the FKB.

Thanks for the follow-ups. I'm waiting for my KD to get back to me to confirm that he meant the warranty on the Boos and not the cabinets. I am willing to forgo the counter-top warranty as it is only for 1 year, but I don't want to void the cabinet warranty.

I can't figure out why it's such a big deal, they put wooden boats in the water all the time.

On attic mag there are several examples of butcher block with undermounted sinks. It is a very beautiful look!

Here is a link that might be useful: Sinks we love at Attic Mag

I was told by Boos butcher block if you do an undermount, even with waterlox on the exposed edge, it voids their warranty. I still gave it serious consideration.

Question to eandhl and others:
We have an undermount sink with butcher block. Currently it's oiled--a mistake I believe. Was thinking of going with urethane though don't like the gloss.

Question is: we have Waterlox on the floors and LOVE it. I have not found any reference to it on countertops, particularly from the standpoint of food safety. I'd love to use it: anyone with advice/experience?