I hope I am not boring any of you with my repeat of this question (well, that's what the delete key is for! :) but this is a burning question in our household! We *have* to make a decision on what we are going to use ASAP. Here's the Q, boiled down: Is there any reason why we should *not* use a clear silicone caulking (or something similar) in between the boards of a prefinished hardwood floor? We do cat rescue and from time to time have "pee-ers" in our house (we have one now), and I want to make darned sure that puddles of pee can't go down in between the floorboards. (Yes, wiping it up would take care of the issue, but they usually do this sort of thing at 3 am.) I particularly want to use prefinished flooring because of the aluminum oxide coating, which I think will stand up to cat claws and everyday life a whole lot better than a urethane finish which is applied in place. Also, to be frank, we can't really afford to have a pro put in a finished-in-place floor, and I think that obtaining a good finish by ourselves may be out of our league. :) Now, the main reasons I can think of *not* to use an elastomeric caulking in between the boards as we put the floor down are: 1) It would be an ungodly amount of extra work. 2) The tiny bit of extra material in there might interfere with the natural expansion/contraction of the wood and cause buckling down the road. 3) The material might be visible in some way later down the road. Dealing with (1) ... is my problem, I guess! :) Dealing with (2) ... I have a hard time seeing how just a little bit of caulking in there would interfere significantly, but I am not a pro, obviously. Also, it seems to me that the majority of the expansion/contraction should take place in the 1/4" which you are supposed to leave around the perimeter of the floor, anyway. I did do a small test on a couple of sample pieces and the caulking really did the job. I used water-based and wiped it off the top, and you couldn't see it at all. When it dried, it repelled water like nobody's business. But I am concerned there may be long-term problems. The other option I have thought of is to go around after the floor is done and dribble some polyurethane into all the cracks. But this seems like just as much work as putting in the caulking, and also I don't think it would repel as well as the caulking, not being as much of a physical barrier. I have tried talking to the manufacturer and they were not a whole lot of help. I had the distinct feeling that they didn't want to go out on a limb in any way (which I can't blame them, but it didn't help me any). If anyone has ever tried anything like this, or especially, if you are or know someone who is a professional installer, I would really like an opinion on this. Thank you! Ann