cement floor thickness

You'd have to tell us a lot more about how these floors are constructed, are they pre-fab, poured, or what?

Pure guess on my part but I'd say backerboard on ... something. I can't imagine any other "cement" floor that could "move".

Judging from your posting address I would guess you're in Poland. Most of the questions that are asked on this newsgroup come from North America and Great Britain, though it is worldwide. With this in mind provide some more information about the construction. What type of floor was put on, how was it put on, what sort of radiant heating, etc. Feel free to post a picture or video to a host site and post the link for us here.

What did the contractor who installed your floor say when you brought up your concerns about the floor?

Anything that 'moves' as the OP describes has got to be really strange! (WHich is why I asked...)

I really liked the: "Dust raises from joints" comment.

on 5/5/2009 3:24 AM (ET) TR wrote the following:

Building Inspector! If he doesn't know, he will find out.

Based on Rico's figuring out that the OP is maybe in Poland.......my guess is deteriorated gypcrete over radiant heating tubing. :(

cheers Bob