Feature Article - May/June 2003

Tread Lightly

A complete guide to selecting the right sports surface

By Margaret Ahrweiler

Talk the Talk So You Can Walk the Walk

If you speak the language, you can communicate more effectively as you do your sport-surfaces homework. Here are a few of the words you'll hear tossed around in flooring discussions.

Point-elastic surface A surface that bends at the point of pressure and absorbs energy. Most synthetic surfaces constitute this.

Area-elastic surface A rigid, nonbending surface that yields gradually to pressure and can return energy, such as wood floors

Composite surface A surface with characteristics of both point and area elasticity, often a synthetic surface over wood

Resilience A floor's ability to bend or give; synthetic surfaces often have greater resiliency than wood.

Moisture content The weight of water contained in wood flooring, as a percentage of a kiln-dried sample

Sleeper system Wood flooring system where the wood strips are installed atop strips of wood studs

Panel system Wood flooring system where the wood strips are installed atop sheets of other material, often plywood

Anchored system Wood flooring system where the wood strips are installed atop sheets of other materials, often plywood, with 2-by-3 "sleepers" under the plywood

Acclimatization The process where wood flooring materials must sit in the facility for a number of days to adjust to moisture levels

Force reduction The ability of a sports floor to absorb the shock of impact, compared to a nonresilient floor

Ball rebound The percentage to which a ball bounced back to the height from which it is dropped, compared to a nonresilient floor such as concrete. Ball rebound, or bounce, should be at least 90 percent on a sports surface where basketball is being played.

Standard deformation The depth to which a floor indents under a load of weight

Deformation control The spread of a deformation, or the area it covers, when a floor indents under a load of weight

Sliding behavior The distance a floor can permit an athlete's foot to turn or purposely slide, while still preventing uncontrolled sliding. DIN standards require floors to have a sliding distance of 0. 4 to 0. 6 meters.

EDPM Ethylene propylene diene monomer, a type of synthetic rubber flooring that comes in granule form

SBR Styrene butadiene rubber, another granulized form of synthetic rubber

PVC Polyvinyl chloride, a common form of synthetic flooring that, yes, is the same stuff of which your plumbing pipes are made

Polypropylene Another form of plastic, often used for sports-flooring squares or tiles

Prefabricated sheet systems or sheet goods Synthetic flooring manufactured off site and delivered in rolls or sheets

Cast in place systems Synthetic flooring systems created on site

Installation and maintenance

Unlike wood, synthetics can be installed without worrying about humidity or acclimatization, heavy equipment or technical expertise, but they have their own set of installation issues.

PHOTO COURTESY OF PLEXIPAVE

Riverside Park in Coral Springs, Fla.

With sheet goods, owners must make sure the substrate base—the concrete—is free of imperfections, since those will come through, and installers must pay special attention to the seals or seams between rolls, which can create weak spots that can trap water.

Poured-in-place systems can cover flaws in the base, but that resulting variation in thickness can vary the floor's performance. The pours also eliminate the issue of seams, but this makes repairs more difficult: Owners can't simply pull up a chunk of floor to fix or replace it. Likewise, poured floors require more quality control during installation.

Many manufacturers and consultants recommend a clear, sprayed-on urethane topcoat to further protect synthetic floors from dust and dirt. While this may increase the floor's shine, it does not affect performance.

For some sports, synthetics have become the flooring of choice. Polypropylene interlocking tiles have become the standard for inline hockey and skating arenas, such as the St. Cloud Sport Center in St. Cloud, Minn., for their friction coefficient, which allows both optimal puck glide and skate wheel grip.

Guidelines for Area-Elastic Sports Floors

1. Force Reduction

Force reduction is the ability of a sports floor construction to absorb the shock of an impact as compared to a nonresilient floor. In this test, the athlete must not be exposed to more than 47 percent of the impact.

2. Standard Deformation

Defines the vertical deformation of the sports floor under load. The minimum deflection required by this test is 2.3 mm.

3. Deformation Control

The area spread of a deformation is measured at a distance of 500 mm from the point of vertical impact (by a falling weight of 20 kg). Maximum deformation difference: 15 percent.

4. Ball Rebound

Defines the height in percent to which a basketball bounces on an area-elastic sports floor as compared to the ball rebound height on a nonresilient floor. The ball rebound should be at least 90 percent.

5. Sliding Behavior

Characterizes the property of a sports floor surface to permit turning movements of the athlete while preventing uncontrolled sliding. Required sliding distance: 0.4 to 0.6 meters.

6. Behavior Under Rolling Load

The ability of an area-elastic sports floor to withstand loads from rollers, coasters or wheels. Minimum requirement: axel load 1,500 N, without damage.

Diagram Courtesy Of HARO sports

Synthetic floors also surface in areas beyond sport courts. They are starting to take hold in aerobic and group-fitness spaces, where their resiliency appeals to users and variety of colors appeals to style-conscious designers.

In weight rooms and cardio-equipment areas, rubberized flooring systems have become popular for their sound- and shock-absorbing capacities. These cushioned systems, which can be made from ground rubber—one firm is marketing a surface made from recycled gym shoes—can come in either rolls or tiles. And since owners don't have to worry about bounce requirements or athletes' joint cushioning, they can take a more budget-conscious approach, says BSA's Ross.


LEFT: PHOTO COURTESY OF MOOSE SPORTS SURFACES RIGHT: PHOTO COURTESY OF GERSTUNG FLOORING
Left: Great Lakes Naval Base's Freedom Hall Physical Training Facility in Great lakes, Ill. Right: Dance studio at the Gerstung Center in Baltimore.

Rubberized flooring also is turning up in children's play rooms at fitness and recreation centers, for its ability to provide grip and cushioning, without the rug-burn issues of carpeting, as well as for its easy cleaning and sanitizing qualities. (Many synthetic surfaces now offer antibacterial finishes.)