How to noise-proof laminate floors in 2nd floor condo?

I just installed laminate flooring in my kitchen and I know that you're not supposed to use additional underlayment if there is some attached to the bottom of your flooring. But- I think I would go with the thicker, compressed cardboard- just because it seems like it would work the best under the laminate, in my opinion.

If already installed, then the best you can do is to have the upstairs person use rugs, walk lightly, and (as someone else said) wear slippers. If not installed, yet, then you can install high quality padding below the flooring. Typically, laminate flooring is put on top of a thin layer on foam. There are thicker foams that do a better job of leveling (which is one cause of noise) and sound insulation. Floating flooring will have some additional noise, unless the flooring is 100% level (which it will not be) because of air cushions between the floor and the under-floor (or, actually, the padding). The person under COULD do something to their ceiling, but this wouldn't do much and would be expensive.

The laminate floor will always make some noise. There is a sound deadoning underlayment that will help but wont completly get rid of it. It's made of rubber. As for the squeaks. Expose the deck, finf the floor joists and run two inch screws into the joists through the deck. That should tighten it up.

my husband and i are contractors and do many many laminate floors, we also have them in our home. the fiber type does help a great deal with the noise and as far as soft underfoot-maybe a little. the very thin white with plastic on one side-sucks. the floors stay cold and they are loud. we use rugs on ours because it looks good and cuts the noise out-not many, just in the high traffic areas. not all underlayment is compatible with all floors-check the flooring box.

That is a tough one... Usually the place should be well insulated when it is built so that noise does not pass through the floor.