Gym Floor Finish Terminology

Abrasion of Gym Floor Coatings or Finish

The action of wearing away the gym floor finish film by friction. Usually caused by particulate soil such as sand, ice melter and dust.

Abrasion Resistance of Wood Gym Floor Finish

The ability of a gym floor coating to resist being worn away by rubbing or friction caused by gym floor traffic and dust. Abrasion resistance is not necessarily related to the hardness of a coating but is more correctly correlated to toughness.

Acrylics in Gym Floor Finish

The most common polymer component of all water-based gym floor finishes. Acrylics offer good detergent resistance and produce colorless films. They are a family of thermoplastic resins of acrylic esters.

Adhesion of Gym Floor Coatings

The attraction of a new gym floor coating to a previous gym floor coating.

Alkaline Cleaner

Any floor cleaner that has pH greater than 9. Use neutral cleaners on gym floor finish

Alligatoring or Orange Peeling of Gym Finish

Gym Finish that takes on the appearance of an alligator hide or orange peel texture after the gym finish is dried. Usually caused by applying a very heavy coat of finish or recoating too quickly.

All Purpose Gym Floor Cleaner (Neutral Cleaner)

Neuetral pH sport floor cleaners that can be used on all sport floor surfaces and usually will not harm the gym floor finish.


Oil-modified urethanes (OMU) have a tendency to darken or “amber” over time. Activated by UV light. This phenomenon usually occurs within the first six to twelve months after the finish is applied.


The property of a gym floor finish that makes a athletic floor non-slip.

Applicator Drag

Drag felt when recoating a gym. This is a sign of applying the finish too early or not keeping a “wet edge”.

Auto-Scrubbers for Gym Floors

A machine that has two compartments, one for a cleaning solution and the other for recovering soiled solution. As the cleaning solution is applied to the floor, rotating brushes or pads scrub the surface and the soiled solution is picked up at the back of the machine with the use of a self-contained vacuum system.

Blushing of the Gym Finish

The formation of a white or grayish cast in a gym finish during drying. Most often caused by one or more of the following: high humidity, improper dry time, too heavy a coat applied or more coats than recommended.

Buildup of Gym Finish Along the Floor Vent Cove Base

Refers to areas of a floor (outer perimeter of the floor) where the gym coating does not wear down, but successive coats are applied.

Burnishing Gym Floors

Enchancing the gym finish shine with the use of a propane burnishing machine. Speeds in excess of 2000 RPM and are required*.


Found in many water-based wood finishes. A catalyst is added to some finishes to bind individual polymer chains to one another, thereby imparting a tougher film without the catalyst.

Chatter Marks on a newly sanded gym floor

Patterned repeated divots in a wood athletic floor caused by the use of a drum-sander. They are caused by part of the drum that holds the sandpaper in place and therefore does not sand the floor. Most noticeable on tight-grained woods with a high gloss.

Chemical Resistance Characteristics of Gym Finish

The property of a gym floor finish that allows it to be unaffected by chemicals that are spilled onto it.


The clearness of the gym coating film.

Cohesion or Inter-Coat Adhesion

The attraction of a gym floor coating to itself.

Compatible Gym Finish

Capable of being used together in a product and having no undesirable effects.

Coverage of Gym Coatings

Measured in square feet per gallon, it is a measurement of how much area a gallon of gym finish will cover according to the manufacturer.

Craters in the Gym Finish

Often mistaken for bubbles. Craters are caused by bubbles that pop but don’t level. Silicone contamination from mop treatments also causes craters.

Crazing or Spider Web effect

The appearance of very fine cracks on the surface of a dried finish film. Sport Wood Crowning Caused by excessive moisture in the strip maple wood floors.

Crowning of boards on a gym floor

Results in the center of the floor boards being higher than the edges. Gym Floor Cupping The opposite of crowning. Also caused by excessive moisture in the wood.

Cupping of boards on a gym floor

Results in the center of the wood being lower than the edges.

Curing of Gym Finish

A term generally applied to the time a wood sport floor coating takes to completely dry and reach full hardness. All gym coatings have varying cure rates.

Dirt and Dust Retention

A gym finish that has high dirt retention when soil from foot traffic becomes embedded into the finish easily and quickly. More prevelent in softer Oil-modified urethnes for gym floors.

Dry Time of Gym Finish

The length of time it takes a gym finish to become tack free, thereby allowing another coat of wood sport floor finish to be applied.

Durability of gym floor coatings

The ability of a gym finish to withstand wear.

Expansion Spacing of Wood Gym Floors

Often called “washer rows”. Since wood expands and contracts depending on moisture content and humidity, these spaces provide an area for the wood to “move” within. Generally, a washer row is placed every two to three feet per face-width of board across the floor.

Expansion Voids Expansion

Voids are areas in a maple sports flooring system where no flooring or sub-flooring components are installed, specifically to provide space for system movement.

Gym Finish

A coating that protects a wood sport or athletic floor from wear and enhances its appearance. Fish Eyes Caused by surface contamination (usually dust) or by improper agitation of finish prior to application.

Gym Finish Flaking

Finish that pulls away from floor in small pieces, usually aided by mechanical action of shoe-twisting on finish. and usually starts at the joints of the maple strip sport floor. Usually very evident on painted keys and school logos. Potential issues can be traced back to paint and finish compatibility.

Flexibility of Gym Floor Coating

The ability of a floor finish to be pliable and resilient.

Gloss level of a Gym Finish

A term use to describe how shiny the athletic surface or film is. In general, the flatter the surface, the greater the ability for light to be reflected off. Shiny gym floors.

Gloss Meter

A device used to quantify how much gloss a surface has at various angles. Inside the device, a light is emitted onto a surface that measures how much light is reflected back. The higher the number, the better the gloss.

Hard Water Can Cause Dull Looking Gym Floors

Water, which contains the ions of magnesium and calcium. When hard water is used in a cleaning system, insoluble materials may form. This is called a precipitate. Hard water is usually expressed in parts per million or grains. 1 grain hard water = 18 PPM hard water.

Hardwood Maple Athletic Floor

A wood sport, athletic, yoga, or aerobics floor made of maple, Birch or Beech.

Heeling a scrubber, buffer, or single disk rotary floor machine

The practice of tilting a floor machine to exert increased pressure on a specific area of a floor. Usually white or black scuff marks on wood or synthetic sports floors.


The measure of moisture in the air.

James Machine

Device used to test slippery gym floors A machine that measures the static coefficient of friction of a floor finish. This is the measure of how slip resistant a finish is. Also known as ASTM test method D2047. The sufficient James Machine reading to indicate slip resistance is 0.5 or greater.


The ability of a gym finish to be completely flat when dry. If applicator marks are evident in a dry finish, it is a sign of poor leveling or poor application techniques.

MFMA –  Maple Flooring Manufacturers Association

M. S. D. S. Material Safety Data Sheet

Required for all products. It lists hazardous ingredients for particular compound and also details safety precautions and first aid information.

Neutral Gym Floor Cleaner

It’s not acidic and it’s not alkaline. Neutral pH means it’s in the 5.0 to 9.0 range, however, a true neutral cleaner has a pH of 7.0.

Non-Volatile Solids of a Gym Finish

Measured in percentage, they are the materials that are left when all water and other solvents are driven off a coating during drying. In a gym floor finish, the solids are what forms the film on the floor.

OMU for Gym Floors

Oil-modified urethane. A popular type of wood floor finish. Contains aromatic urethane in a solvent (oil) base. The solvent is usually mineral spirits or a similar petroleum distillate.

Panelization of a Gym Floor

In a gym floor, the action of the boards to separate in groups. Often occurs at the subfloor joints. Also known as sidebonding.

Peeling Gym Finish

The pulling away of a film or coating from its substrate caused by a lack of adhesion. Can be caused by poor prepraration, prior contamination, pulling tape off the floor,


Small pock marks, usually spread evenly across a floor. Dust specs are a major cause, along with improper dry time between coats.

Pot Life

When a catalyst is added to a water-based wood finish, there is a span of time when the product can be safely used. This time span is known as pot life. Although it will vary from product to product, it is usually from two to 18 hours.

Powdering of Gym Finish

The disintegration of a finish that results in a fine powdery substance. Poor bonding (adhesion) of the finish to the substrate (floor) is a major cause. It can also occur during burnishing when a finish is not fully cured or when an improper or poorly maintained polishing pad is used.

Recoating a Gymnasium Floor

The process of applying multiple coats of gym finish over one another to increase the appearance and protection of the sport flooring.

Sand Screening for Gym Recoating (preparation)

The use of a buffer or swing machine with a sanding screen to sand a bare wood floor as a final step before sealing. It is also used to deep clean and roughen a floor when recoating with certain finishes. Sand screens range from very coarse (40 grit) to very fine (240 grit).

Scuff Marks on a gym floor

White or Black Occur when a person walks without lifting their feet. A finish that is hard to scuff is said to have good scuff resistance. Shelf Life The length of time an unopened product will remain unchanged in its container after packaging.

Sidebonding of gym floor boards

See Panelization.

Slip Resistance of Gym Finish

The frictional force opposing movement of an object across a surface. In the floor finish industry, this usually refers to how easily the heel or sole of a shoe slides across a finish. A value of 0.5 or greater using the ASTM D2047 method is considered safe for walking on.

Solvent Rain-Back

Phenomenon that can occur 6 – 24 hours after finish application when humidity is high and air flow is low. The volatile components within a finish (solvents) can redeposit on the floor, leaving an oily (slippery), dull look.

Streaking of Gym Finish and Coatings

A dull, hazy appearance caused by finish applied too thinly or insufficient dry time between coats. Mostly caused by poor gym floor coating technique.

Tack Rag

A cloth moistened with a liquid or water used to remove dust from a floor before coating. Tackiness of Gym Floor Finish Another term for describing a coating that’s sticky. Before a coating is completely dry it will go through a tacky stage.

UL (Underwriters Laboratories)

Underwriters Laboratories (UL) is an independent, not-for-profit product safety testing and certification organization. They test Essential floor care products as to their slip resistance.

Total Solids of Gym Finish

All materials in a cleaner or finish that remain after all water and solvents have been removed. V.O.C. Volatile Organic Compounds. This is a measure of the non-water solvents that are in a particular product.

Viscosity(Gym Finish)

Gym floor finish Refers to how thick or thin a product is. Different scales are used to measure this property.