floating floor question

[dkpbxman]

I plan on putting down a laminate wooden floor over my concrete slab. From everything I've read, the slab needs to be almost spotless before-hand.
Is this the case with floating installations, where nothing is actually attached to the concrete or can I just level out any dips and rises, put down a vapor barrier, underlayment/cushion and then the laminate?

Thank you

 

[Square Eye]

Yep. Get a rubbing stone if you find any ridges or lumps or bumps you can knock them down with it. Lay a flashlight on the floor and you will find all kinds of imperfections on an average slab. Lumps and bumps can penetrate a vapor barrier. Your next big issue will be trying to keep it dry. If your flashlight reveals low spots, these could become puddles under ther floor later on. Consider all of the possibilities before you decide exactly what you want.

Good luck, Post some pictures if you do it.

 

[dkpbxman]

I'm sorry, I worded the question badly.

Is it O.K. if I not worry about a little material left by the, probably 30 year old, underlayment (which seems to have bonded to the concrete in spots) even after strenously scraping, as long as I make it flat?

I've been told that roofing shingles are good for that. ???


If I can figure out how to upload pictures, I will.


Thanks for replying