Highlights

• New 20,000-seat Toyota Park soccer stadium installs Uponor turf-conditioning system
• 85,000-square-foot playing surface will remain soft and forgiving to falling players even in colder months
• Contractor Althoff Industries buries 168 loops of Uponor's Wirsbo hePEX™ plus tubing approximately one foot below the 425-foot-long playing surface

Background

Kicking off every April, the bulk of the seven-month Major League Soccer (MLS) season occurs in spring and summer. However, if a team reaches the post-season playoffs, they could find themselves running and tumbling in the cold and wet of late fall. But no matter how bad the conditions, the owners of the Chicago Fire MLS franchise want their new $70 million Toyota Park to look and play every bit as well in October and November as it does in June or July.

This is why the new 20,000-seat stadium features a state-of-the-art turf-conditioning system that will keep the playing field in superb, player-friendly condition year-round. Manufactured by Uponor, the system was installed by Althoff Industries of Crystal Lake, Ill., which built a similar system in nearby Soldier Field, home of the NFL’s Chicago Bears. Uponor helped on that project, too. “Uponor makes a great product,” says Althoff senior vice president Chris Bennett, who supervised both projects. “Plus, we have always relied on their engineering expertise and factory support. That’s why we stick with them.”

How the System Works

The turf-conditioning system circulates a warm, water-and-glycol mixture through 168 loops of Uponor's Wirsbo hePEX plus tubing, buried 10 inches below the surface and spanning the length and breadth of the 200-foot by 425-foot field. On sunny days, the demand for warmth varies across the field’s four heating zones, depending on the position of the sun.

Two temperature sensors in each zone communicate an average demand back to a series of control valves, which respond by modulating the flow of warm water from two, commercial-grade boilers located beneath the stands. The result: The subterranean root zone remains at a consistently comfortable 65°F (18°C) – warm enough to grow grass in the dead of winter. The playing surface remains forgiving to falling soccer players, even at sub-freezing temperatures.

“The freezing point for the glycol mixture is minus-25 degrees, so the system can be filled with fluid year-round, without the hassle and expense of draining and refilling it prior to each season,” says Bennett.