typical values for floor flatness/levelness

[MikeE55]

What values are reasonable for an office type floor, not a warehouse? According to ACI Concrete Knowledge Center, Ff = 20 and Fl = 15 are "conventional numbers." This would be equal to a 5/16" gap under a 10' straightedge, which seems excessive, but maybe that is typical. I would like to hear what numbers you normally specify, and if they have been verified by a lab as actually achieved. Thanks for your feedback.

 

[Ron]

Ff=25 to 30, Fl=18 to 20 will get in a reasonable range, somewhat near or slightly better than 1/4 under 10-ft. straightedge.

When you exceed these numbers, it requires more control in the placement and finishing process, that might not be worth the extra effort/cost, particularly for general office use.

 

[BAretired]

The floor must be finished to some reasonable standard. A deviation of 1/4" in ten feet has long been a specified standard, but in the last fifty years, I cannot recall anyone ever checking to see if the floor complies. It is a good idea to have something in your spec just in case you get a really wild floor finish and the contractor wants to argue that it really is okay.

Best regards,

BA

 

[geoffdale]

Depends what type of flooring you are putting down. If its carpetting- I would think the lower values would be just fine.

 

[BigH]

http://www.cca.org.nz/pdf/Cooks_Clinic30-31.pdf

http://www.concrete.net.au/publications/pdf/Tolerances.pdf

http://www.cca.org.nz/shop/downloads/SpecifyingConcreteforPerformance.pdf

(concrete details, not regularity although it references surface regularity)