procedure for floating floor on uneven concrete slab

My builder is half way through installing floating floors on our concrete slab. The slab is uneven, at the really bad part he put "screed" (if that is correct) to even out a small portion however no where else. On the portion that has been laid it is bouncy and in one area appeared to crack when we stood on it. There has been no moisture barrier put down and the underlay is a very thin white plastic sheet.

I am concerned that the floor is going to break when heavy items such as furniture is placed on it and am concerned that there may be moisture coming up as well.

I have looked at the timber flooring association web site to see if I can find some standards/guides about installing floating floors over uneven concrete but can't find a guide.

Am I unnecessarily concerned or would you be upset if this was your place? Can anyone direct me to some information about how this installation should be done.

thanks!

The underlay could be the kind that is a moisture barrier as well.
Quickstep.com/australia has laying instructions. Have a look around the site.

What type of flooring, which brand?
Timber or laminate?

The white underlay is all you need for the moisture barrier, that’s what it’s designed for.

http://www.google.com.au/search?hl=en&s ... =&aql=&oq=

We've layed floating floors on pretty uneven slabs. The foam underlay takes up a bit of the humps and bumps though I still think it feels springy and will
never settle down and feel right. My opinion is to get a concrete grinder in to take off the humps. You could also fill in the low spots with self level before he comes out and he can take any off that is still high. He won't get it perfect but will make a huge diffference.

Marcos, I like your groove. I agree, get them to knockoff the high points with a grinder and self-leveling cement, but it's not cement, it's a polymer. It will cost them some big $$ ( say $50-100 /m2), but it's your floor. Dont let them cow manure you. It's a simple question to ask "Why cant my slab be level like the slab next door? - What went wrong?"

I suggest levelling compound as well.

Thank you for all the responses. The slab was a pre existing one, we had another slab added in the extended portion which is level. There was a 4cm difference between old and new (flat slab). He levelled out the really bad part but the rest wasn't great.

Not aware of the brand but it is floating timber not laminate. Good to hear the white underlay is a moisture barrier. I guess time will tell if it stands up, hope it's covered by the 7year guarantee!