In the downturn of our economy many flooring contractors are looking to different materials to keep their installation crews busy. Some of them are looking at the sports flooring market. Sports floors are available in many different types and require many different installation techniques. Unless a flooring contractor is prepared to deal with all of these nuisances and challenges, they should stay away from this category. Failures on these types of jobs can be extremely expensive.
The requirements for sports floors vary somewhat from normal resilient installations. The materials can be made from rubber, vinyl or urethane with layers of one to three layers in thickness. Product resiliency can vary depending on its intended use. So whether the product will be used in a gymnasium, multipurpose room, field house, fitness room, tennis court, or indoor jogging track, the sports floors can have both slip and non-slip surfaces.
The recommendation for substrates is very standard through the sport flooring industry with a strong emphasis on quality substrates. Some of the requirements are as follows:
Concrete substrates need to have a flatter surface than what is required for normal resilient surfaces. Most of the manufacturers recommend a 1/8” in 10’ rather than the traditional 3/16” in 10’. The higher tolerance is to prevent injuries to the athletes and other sports floor users. The concrete surfaces needs to have a slight texture to it to insure the adhesives achieve a good bond, which can be difficult when adhering to a hard troweled or burnished concrete surface.
Wood substrates need to be suspended with a minimum of 18” (47cm) of cross-ventilated air space between the joists and the ground. Exposed crawl spaces should have a polyethylene ground cover. This is important because the sports floor is a very effective vapor retarder and will allow any moisture to develop beneath the material and have an adverse affect on the wood underlayment. The underlayment needs to be a minimum of 1/2” thick and should meet the requirements of the APA – Engineered Wood Association. The use of oriented strand, particle or chipboards, as well as softer plywood such as lauan is strongly discouraged, due to the heavy stress that will be placed on the substrate.
Lightweight concrete needs to be dry. Remember a lightweight concrete will take twice as long to dry as a normal weight concrete. It is highly recommended to always do a 72-hour bond test on all lightweight concrete to insure it meets the bonding requirements.
Sports flooring contractors should be very familiar with American Concrete Institute, ACI 302.2R-06 “Guide for Concrete Slabs that Receive Moisture-Sensitive Flooring Materials” and ASTM F-710 “Standard Practice of Preparing Concrete Floors to Receive Resilient Flooring.” The areas to be installed with a sports floor should be constructed to meet or exceed the requirements of ACI 302.2R-06 and the preparation of the substrate needs to follow ASTM F-710.
Moisture testing is a must. The preferred method for moisture testing is ASTM F-2170 with results not to exceed 75% relative humidity. And almost all sport flooring manufacturers recommend a 72-hour bond testing as well. Many of the manufacturers are moving away from the ASTM F-1869 calcium chloride testing in favor of the relative humidity probe test. pH testing also needs to be done, with a pH test result ranging between 5-9.
Concrete joints need to be dormant, the slab needs to be acclimated and the HVAC systems need to be on and balanced. Failure to follow these installation requirements can result in a joint movement problem for which there is no easy cure.
Sports flooring adhesives are very specialized. They range from acrylic to urethane, polyurethane to epoxies. Most resilient installers can deal with and understand the characteristics of an acrylic adhesive, but urethane and epoxy adhesives require a lot of experience and attention to detail. Familiarity and knowledge of the backing types used on sports floors also require specialized installers.
When working with sports floors you need to have specialized equipment for moving and storing the rolls due to their weight. The rolls need to be secured and stood on end until they are ready to use. All pieces need to be kept rolled face out on a core until ready for use. The materials need to be acclimated in environmental temperatures between 65ºF and 85ºF (18º to 29º C). Since the area to be covered is large, the installer must pay close attention to end seam placement and sequencing of rolls to prevent any shading issues.
Heat weld seaming is the preferred method to finish the seam. Heat welding a sports floor will vary from material to material each with its own characteristics and settings. The most important aspect of heat welding is the depth of the groove. Many installers, even those familiar with sports floors, tend to cut the groove too deep. The depth of the groove should not exceed two-thirds the thickness of the wear surface of the material.
The welding temperature used for sports floors is a little cooler than that used for commercial sheet vinyl. And finally, and most important of all, most sports floors have a urethane finish. When welding these materials scorching is a big concern. Manufacturers often recommend special weld tips to prevent scorching and to yield high seam integrity. Be sure to check with the manufacturer for types of weld tips available designed specifically for the flooring material you are using. The narrow preheat tips are becoming more popular for the welding of urethane surfaced materials because they focus the heat into the groove with less hot air washing out onto the material’s surface.
The final touch to a sports floor is the painting of the lines. This is a specialized art and requires hours of attention to detail. The paint must flex with the surface material, have the same elasticity as the material, and be compatible with the surface finish. Any failures in this part of the installation can be a disaster.
If you are looking to go into the sports flooring business, make sure to spend plenty of time researching the nuances of this specialized category. Then, if you want to pursue this segment, plan on getting your installers lots of training. That’s the only way to hit a home run.