Floor level and engineered wood floor

[Kimberley88]

Can someone give me an idea of how flat / level the floor needs to be to lay an engineered wood floor. I have used screed to get it flat as possible but its still not perfectly level, is there a degree of tolerance that is acceptable.

Hope the above makes some kind of sense.

 

[WoodYouLike]

Makes a lot of sense.
You are allowed 3 - 4 mm gradual drop per linear meter if your floor is sloping.

 

[Kimberley88]

Thanks woodyou like,

My floor is bitumen and even after using screed which improved it quite a bit its still quite wavy, I used a long plank and can see it dips up and down, is it worth me putting plywood down first, although I am not sure how I would fix this to the floor or what thickness to use. Any ideas please.

 

[WoodYouLike]

Plywood is an idea, but you could also place thin extra underlayment (2mm foam) on those spots that dip. It will take a bit of trial and error (cause sometimes the extra underlayment in one spot will raise the floor in another spot, but keep trying till you find the right place and amount of extra underlayment).