Concrete floor flatness and levelness

Concrete floor flatness and levelness Download PDF EPUB FB2

Elevation differences are measured every feet within 72 hours after the concrete is placed and those measurements are entered into a calculation to determine floor levelness (FL). Higher FLnumbers indicate a more level floor and the numbers are linear so a FLof 50 is twice as level as an FLof Flatness relates to the bumpiness of the floor, while levelness describes the local tilt or pitch of the slab.

The higher the F- The higher the F- Number, the better that characteristic of the floor. Floor Flatness & Levelness One of the things that distinguishes a high tolerance floor is its F-number requirement. F-numbers were developed in the s to provide a systematic, quantitative way to indicate the flatness and levelness of a concrete floor.

The higher the F-number, the flatter or more level the floor. Surface regularity, as defined in terms of levelness and flatness of an unformed ground or suspended slab surface is important to satisfactorily apply flooring materials or, in the case of a wearing surface, for traffic and people to circulate safely.

The slab must also be constructed within a. Floor flatness (FF) and floor levelness (FL) are measurements by which architects can hold concrete placement contractors accountable and provide a quality control level during the initial placement of concrete slabs. There is a difference between the two.

When explaining this to my customers, I often use a pool table as an example. Some of the industry misconceptions for floor flatness and levelness are the following: 1. The ASTM that directs how the FF and FL values are to be collected and calculated is ASTM E - Standard Test Method for Determining FF Floor Flatness and FL Floor Levelness Numbers (Ref.

1).File Size: KB. Floor Levelness tolerances, evaluate the effect of different construction methods on resulting floor surface flatness and levelness, and investigate the curling and deflection of floor surfaces.

3 These F-Numbers use dimensionless symbols to designate both flatness and levelness and are designated as. In addition to the floor flatness criteria, there is also a structural deflection concern wrongly associated with floor levelness.

Suspended floors deflect and all slabs can change shape significantly in the first few days of placement, which is the reason flatness is measured within 72 hours and before shoring is removed from suspended slabs. cumulative along lengths greater than 10’-0”.

Finally, the straightedge specs do not address floor flatness (roughness or wash boarding) or levelness (tilt or slope). What are F-Numbers. The F-Number system is a statistical method of evaluating horizontal concrete surfaces for flatness and Size: 1MB.

Flatness tolerance: FF or gap under straight-edge, depending on the floor profile class. ACI requires no level alignment tolerance for the concrete because levelness depends on the location and placement of the supporting structure and, after the concrete is placed, deflection of the supporting structure.

The steel, precast erector,File Size: KB. 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.

Common tolerances were 1/8 inch or 1/4 inch in 10 feet. The fallacy of the straightedge method was the location of the measurement. Depending on where the measurement was made, the slab may pass or fail the specified. Surface regularity - levelness and flatness.

The surface profiles of a slab need to be controlled so that departures from a theoretical flat plane are limited to an extent appropriate to the planned use of the floor. Levelness and flatness tolerances define the allowable or permitted variation in of a floor surface. This saves lot of time of customer to start the operations on newly constructed floor.

Our latest testing machines produces results of mandatory tests like soil/ ground compaction, concrete air content, concrete strength, floor flatness and levelness results right away on job site. So, when it comes to Flooring, trust only the best.

—Finishing Class 8 floors (two-course unbonded) —Finishing Class 9 floors —Toppings for precast floors —Finishing lightweight concrete —Nonslip floors —Decorative and nonslip treatments —Grinding as a repair procedure —Floor flatness and levelness —Treatment when bleeding is a problem.

ACI Concrete Flatwork Finisher and Technician Certification; Chapter 1 – Planning for slab-on-ground placement; Chapter 2 – Concrete materials, mixture proportioning, and control tests; Chapter 3 – Preparation before placing concrete; Chapter 4 – Floor flatness and levelness; Chapter 5 –.

Section may contain the most important tolerances in the standard for floor slab contractors-the flatness and levelness requirements for various classes of floors, including FF and FL values. Any contractor who is subjected to F-number requirements should study this section in detail.

The Somero Matson Group has created this video free of charge for anyone who is interested in learning more about testing Floor Flatness (FF) and Floor Levelness (FL) within the. First used on a large-scale commercial project inthe F-number system for measuring floor flatness and levelness has been perhaps the most significant factor in enabling the construction of flatter and more level concrete floors.

However, because the dimensionless F-numbers are derived by processing the data from a large number of measurements, it can be difficult to grasp exactly what the. The flatness is the bumpiness or, conversely, the smoothness component, which translates into how much jitteriness the truck operator would feel as the wheels move over the floor.

The levelness is the levelness between the wheels, which controls the forklift's lean. Note 2: When the traffic patterns across a floor are random, (as is generally the case) evaluation of the floor's F F Flatness and F L Levelness will necessarily involve a random sampling of the surface, since all of the infinite potential profiles to be seen by the traffic can not possibly be measured.

In those instances when the traffic across a floor will be confined to specific paths, however, the requirement for random.

Visit The Flat Floor Library™ at for more information on F-Numbers, sample FF / FL specifications, other concrete floor tolerances and helpful documents on flat concrete floors .RE: Floor Flatness and Levelness and Deflection thaidavid40 (Structural) 12 Feb 16 In these parts we normally don't specify an F f value for elevated or suspended floor slabs, just the F l value, because of the deflection complications.For concrete slabs receiving resilient floor covering, therefore, it is most important to describe limits of floor flatness.

In practice, FF and FL values generally fall between 12 and The scale is linear, so that relative flatness / levelness of two different floors will be in proportion to the ratio of their F-numbers.