Building Better Tennis Courts

Lower Bros. Co. uses Bobcat laser-controlled grading equipment to build tennis courts.

Laser-controlled Bobcat grading equipment is essential to the ability of Lower Bros. Co., Inc., to meet strict standards for constructing quality tennis courts in a cost-effective manner.

The family-owned business, based in Birmingham, Ala., has been building public and private tennis courts since 1965. It also has the distinction of being one of the earliest — if not the first — to use a Bobcat loader and grader attachment with a laser system. That was in 1990. Currently, the company owns three Bobcat grader attachments. All are outfitted for laser operation and are used with Bobcat 763 skid-steer loaders. The equipment was purchased from Loader Services, Birmingham.

The company's list of clients includes homeowners, municipalities, country clubs and schools such as Vanderbilt University, Auburn University and the University of Alabama. This work has earned Lower Bros. several "Outstanding Tennis Facility" awards from the American Sports Builders Assn.

Compact Bobcat equipment is ideal for meeting the demands of grading the 60 x 120-ft. base of a single tennis court, says Linn Lower, who operates the company with wife Dana, son Wes, and cousin Cliff. His crews use the laser controlled Bobcat grader attachment to grade the 4-to-6 in.-thick stone base material for the courts. Typically, this base is covered with a 2-in.-thick layer of asphalt and then a colored acrylic playing surface.

"For proper drainage and playability the United States Tennis Assn. requires that the playing surface must lie in a uniform plane with a 1 percent slope," says Linn. "Also, the finished grade can't vary more than 1/8 in. within a distance of 10 ft. That's a pretty tight tolerance. To achieve that, we need a laser system to grade the stone base."

Having laser receivers mounted on both ends of the blade of the Bobcat attachment adds to the accuracy, he notes. "Some systems have only one receiver mounted in the middle of the blade," he says. "Two receivers allow for finer adjustments of the blade because each side moves independently and automatically."

The improved grading precision also improves the quality of the stone base. "A tennis court is more stable if the base is a uniform thickness," Linn says. "You don't want a base that averages 6-in.-thick with some areas 2-in.-thick and others 8-in.-thick. We also grade the dirt subgrade before the stone is installed. This minimizes any differences in thickness in the actual base material."

Before switching to the laserequipped Bobcat grader attachment when grading the area, crews would use a surveyor's transit to shoot a 15-ft. grid throughout the tennis court pad. "We used numbers on paper to figure out where the high and low spots were," Linn says. "Then, we'd rework the grade, shoot it again and keep repeating the process until we reached the desired grade."

Now, he says, setting up and grading the site is a one-person operation. The operator sets up the laser, dials in a 1-percent slope for the laser beam and adjusts the height of the laser transmitter. Then, as he grades the area the laser receivers adjust the height of the grader blade in response to the plane of the laser beam.

"With the laser system, one operator can grade in one day what it would take us two to three days, or sometimes more, to grade using two people with hand surveying techniques," Linn says.

Another way the speed and precision of laser-control speeds up the process is by minimizing the need to re-wet the stone material while working it. "Before, we'd work the stone so much that it would dry out and we'd have to keep re-wetting it to keep the fine particles from dropping out of the mix," concludes Linn.