Concrete floor flatness

[krugger]

Is there any specification for a new concrete floors flatness that is leveled by hand trowel? eg flatness variation over 1m
Also if the floor has got some frost damage and is flaking in places is there any allowance for this. is it acceptable or not.
Cheers

 

[noseall]

depends on what you want to achieve with the finished floor. power floated floors can be finished like glass. hand trowelled ( good enough for most garage floors) tend to have trowel marks and can "dust".

 

[krugger]

had a conservatory built but the floor is not level enough for laying wooden floor plus it flaking. jsut trying to find out how flat it should be and if its aceptable for the surface to flake. going to get them back but want to know how it should be incase thay say its ok

 

[noseall]

its not unusual for some troweled floors to flake or dust,( usually due to excessive water present after final troweling) because the builder doesn't want to hang around till 3 am waiting for the concrete to hydrate. just give it a stiff brushing and apply a few coats of pva to stabilize the dusting.

 

[krugger]

when i say flakes i mean pieces 5-6mm deep inch wide over an area of 2 foot square does that sound like what you say is normal?

 

[noseall]

if you're so worried about pitting then apply floor levelling compound to the offending areas, but lay it, to allow enough time for it to dry out completely, but not too long as to allow too mutch traffic on it ( its only a sub floor remedy and can degrade). there is a more expensive, more tolerant latex based compound if you want a more robust finish.