Modern machinery, robotics, and complex logistical systems increasingly require a transition to a superflat floor measured at a very high degree of flatness and levelness. We are experts at achieving the strictest superflat specifications, using state-of-the-art equipment and a time-tested, proven process. The best part? Our competition can’t match our pricing.
The superflat classification
Defect across 10 feet at Ff 100
The window to measure a new pour
Floor specifications critical to a particular intended use can be identified, controlled, and met using the F-Number System. Correctly understanding and implementing that system is the only real way to be sure the intended use can actually be achieved.
The F-Number System is the industry-adopted standard for specifying and measuring concrete floor flatness and levelness. F-Numbers range from zero to infinity and describe how a floor measures — the higher the number, the flatter the floor. Flatness is written first and notated Ff; levelness follows and is notated Fl.
Ff represents the bumps and grooves in the floor: how close to planar the surface actually is, taking into account amplitude and wavelength. It is a statistical representation of waviness. Elevation change is measured every foot, within 72 hours of placement, and a standardized formula produces the resulting number. Ff is linear — a floor at Ff 80 is twice as flat as a floor at Ff 40. It can be attained on slabs on grade and elevated slabs alike, and it is critical anywhere equipment must be set perfectly level.
Fl indicates tilt or pitch: how closely the finished floor matches the intended slope described in the design documents. Elevation differences are measured along a sample line at 10-foot intervals. Fl is also linear — Fl 50 is twice as level as Fl 25.
A corrected slab, remediated to specification and textured for intended use.
With passing time, joints and cracks curl and the floor becomes less flat. Flatness and levelness should be measured within 72 hours of placement, and preferably within 24. Miss that window and any Ff/Fl numbers you collect may not accurately represent the floor at all.
Fl generally refers to slabs on grade. Elevated slabs are often designed with camber, which becomes a concern once support staging is removed and the floor sags to its final shape. Fl is only specified on an elevated slab where measurements were taken before shores and forms came out, and only where no camber exists.
The structural slab must be placed first and allowed to deflect to its final shape, then followed by a topping finish slab. That topping is what gets measured — and the resulting Fl communicates the separation of the floor from the original slope or plane.
Where your specification sits, and what that number looks like on the floor.
| SPECIFICATION | CLASSIFICATION |
|---|---|
| Ff 35 / Fl 25 | Moderately flat |
| Ff 45 / Fl 35 | Flat |
| Ff 60 / Fl 40 | Very flat |
| Ff 80 / Fl 60 | Super flat |
| F-NUMBER | APPROXIMATE DEFECT ACROSS 10 FEET |
|---|---|
| Ff 25 | A single 1/4" defect |
| Ff 50 | A single 1/8" defect |
| Ff 100 | A single 1/16" defect |
One thing to understand: just because a specified floor was signed off on and paid for does not always mean it measures as flat as it is supposed to. The only way to be sure is to measure floor tolerances properly, with state-of-the-art equipment.
With the rapid advancement of machinery, robotics, and complex logistical systems, superflat floors have become critical to efficient operations. The flatness of your slab determines which racking and logistics systems you can use at all, how much maintenance your equipment demands, and how much you spend on repairs.
Impacts how fast fork trucks, robotics, and other equipment move through the facility
Minimizes the risk of rack impacts and handling errors
Improves overall operational safety
Allows for taller storage systems and, potentially, tighter aisles
Creates faster, more efficient operations and maximizes profitability
Opens the door to modern robotics and rapid picking systems
A time-tested, proven process — from first measurement to documented turnover.
We measure the existing floor and identify every high spot, curled joint, and out-of-tolerance area against your specification.
We model the surface and plan the cut so the minimum amount of material comes off to reach the specified Ff/Fl.
Our equipment removes high spots and corrects curled joints and cracks, working aisle by aisle or across the full slab.
We finish to the surface texture your operation calls for, rather than leaving a raw ground face.
We re-measure and issue reporting that shows the corrected floor meets specification.
The area is cleaned and returned to service — finished, not just ground.
Texture is matched to what runs on the floor, not applied uniformly.
Remediation removes the defect. Texturing determines how the floor behaves once your people and equipment are back on it.
Wheel grip for material handling equipment
Slip resistance in pedestrian routes and transition zones
Consistent appearance across corrected and uncorrected areas
Correct profile where a coating or secondary flooring is planned
When the conversation turns to very narrow aisles, the identifier changes. Defined-traffic floors are specified using the ACI F-min system, which applies only to defined traffic. Ff/Fl and F-min are altogether different measuring systems — there is no direct correlation between them and no corresponding index for comparison.
For random-traffic floors, Ff 100 / Fl 50 is used to reference perfect flatness. If your building runs defined traffic, our VNA grinding and laser milling service is where to start.
It depends on the project’s stage of development. For projects in the first stages of construction, we measure the site and outfit the client with a custom logistics plan so construction starts off on a level foot. For projects already built out, we measure floor flatness and levelness to determine the extent of remediation required. Remediation then comprises milling and grinding the substrate until the ideal texture for proper flatness is attained.
A perfectly level floor is not to be underestimated. In defined-traffic facilities like distribution centers, a flat floor gives forklifts and scissor lifts a smoother surface to run on, which reduces spills and collisions and allows quicker transport — product gets out the door sooner.
Investing in flatness early also means less time fixing problems later. If you want to install tile or any secondary flooring, a contractor working over an uneven floor spends hours correcting inconsistencies just to reach square one. Those hours are your expense. Let Superflat start you at square one.
A level floor is a safe floor. In a busy warehouse, an uneven patch is easy to overlook, and it takes only seconds for an employee to trip or for a top-heavy piece of equipment to lose its footing. Accidents like these happen daily and cost far more than repairs and lost product. An even floor is not a luxury — it is essential in any facility that values the safety of its people.
Flooring is often treated as an afterthought. But floor levelness is increasingly tested during routine construction inspections, and the floor is literally the base your business is built on. A level floor creates efficiencies in both time and money, and a safer workplace with it.
Possibly. A floor that was signed off and paid for does not always measure as flat as specified, and slabs curl and settle after handover. If you are installing robotics, AS/RS, or VNA racking into an existing building, measure before you commit.
Send us your specification and intended use. We’ll tell you the extent of remediation required.