How level does the floor need to be for Laminate?

[wipeoutdude]

Hi,

About to put down some laminate flooring (8mm) through most of the house.. I have found a few areas where the old concrete/cement floor has some dips or bumps and isn't 100% level..

Looking in the shops I see some of the underlays sat they help even out the floor.. Seems there are underlays from 2mm to about 6mm thick..

So how close to level does the floor need to be?

If I have say a 5mm dip over a 2m span is that too much? Do I have to use self levelling compound to build these areas up?

What is the best type of underlay from a cement concrete floor that has these type of undulations?

Thanks for any help..

 

[seasickstevie]

If you're only using 8mm laminate, then it's going to deflect easily when walked on. Therefore you're likely to end up with a rather less than satisfactory feel under your feet to say the least.

Before you start putting any laminate down, you need to get it 'dead' flat.

I don't think it's necessarily 'leveler' you want, but a good 'smoother', the manufacturer's recommended primer, and take your time to get it right.