Floor fl atness is initially measured within
72 hours after concrete placement using
F-numbers to determine contractor’s
compliance with Division 03 specifi cations.
Flooring installers need a fl oor fl atness
metric when they arrive onsite to install
fl ooring in compliance with Division 09
specifi cations. However, because concrete
fl oor fl atness decreases with time due
to curling or defl ection, the initially fl at
fl oor placed by the concrete contractor
is unlikely to meet the fl oorcovering
specifi cation requirements.
