How much unevenness can be tolderated?

[apul]

I've been trying over the last week to level the kitchen floor. I've ground off a high ridge so its just say flat. I've applied self leveling compound (one lot didn't self level so well) and also filled in spots/areas that were still low.

Now I'm left with an almost level floor with some undulation no more than 2-3mm.
Is this acceptable? Could this pose a problem even if I use a thick bed of adhesive to take up the difference?
Also what kind of thickness am I looking to lay on for non flex on solid screed?

Thanks.

 

[BENNY BOY]

The BS standard for flatness of a floor is no more than + or - 3mm over 2 metres and the thickness of the adhesive should be around 6mm bed depth if you need to bed up then a good adhesive is Bal PTB flexible.