Super Flat Floor Tolerances

Concrete floor slab flatness and levelness traditionally allowable tolerances of concrete floor slabs were determined by checking the slab surface with a 10 foot straightedge.

Super flat floor tolerances. Subsurface tolerances and floor flatness requirements a case for cementitious self leveling underlayments by john d. F numbers were developed in the 1980s to provide a systematic quantitative way to indicate the flatness and levelness of a concrete floor. Routinely placing very flat and super flat floors requires an understanding of floor flatness and how to properly use the equipment. This is based on defining a floor s maximum variation for a certain lift truck.

Class 9 floors are superflat and require critical surface tolerances. Understanding specifications for. The most common tolerance is f min 1 0 0 with f m i n 50 being about the lowe s t number used. Gallup ctc csi architectural consultatnt custom building products.

If you have input on the specifications i recommend a 45 ff average or better. The highest number i generally see is an ff 70 which is considered a super flat floor by aci. Ex a m p l e. A specification may identify one set of tolerances for a warehouse floor a different set of tolerances for a television studio and a third set of tolerances for general office space.

Narrow aisle distribution centers with high racking systems fall into this category. F m i n 1 0 0 o r f m i n 6 0 the higher the number the flat ter a n d m o r e level the floor. The ff117 fl110 floor profile on the right exhibits the typical flatness levelness of a super flat floor. The fallacy of the straightedge method was the location of the measurement.

These slabs generally are very uniform in the depth of grind and have a very even aggregate exposure. Common tolerances were 1 8 inch or 1 4 inch in 10 feet. The ff30 fl20 floor on the left is a moderately flat random traffic floor tolerance. Depending on where the measurement was made the slab may pass or fail the specified.

Floor flatness levelnessone of the things that distinguishes a high tolerance floor is its f number requirement. Defined traffic superflat floors must support vehicular traffic along paths defined before construction and don t change during the floor s life. More importantly it requires practice and continuous self. A superflat floor is built to a much tighter tolerance than a normal floor slab using a special tolerance system called the fmin tolerance system.

L re q u i re m e n t s superflat is a minimum tolerance and should be w r itten as follow s. At custom building products we believe substrate flatness is best achieved through the.