The Allegiant Stadium, home of the Las Vegas Raiders completed in 2019, offered a unique challenge for the design team to overcome. The field was intended to be on a rolling tray system that could move inside and outside of the stadium. This state-of-the-art feature would offer a natural grass playing field that, when moved inside the stadium, provides outdoor event space for fans. HNTB architects were up for the challenge and developed a retractable field where 3 feet of sand, soil, and impeccably grown grass could spend time outside, in growing position, or inside, in a playing-field position.

The unique 86,000 sq. ft. retractable field tray was waterproofed with Monolithic Membrane 6125® hot rubberized asphalt. In addition to the field tray, five different areas of exterior terraces totaling 80,000 sq. ft. throughout the stadium rely on MM6125® for watertight integrity.

From Architectural West Magazine: “The whole process, from the planning to the execution, was incredibly scientific,” said Paul McKellar, vice president of Eberhard Southwest Roofing.  “The grass has to be perfectly flat and kept green at all times.”

While the field tray was always specified for hot rubber, the terraces originally called for cold-applied products.  However, Eberhard advocated for a thicker, more durable option with MM6125.  “Hot rubber is far and away the best for this type of horizontal, flat surface,” explained McKellar.  “Here in Southern Nevada, we use American Hydrotech pretty extensively.  We like it because it is thick, self-healing, and can be used on a variety of projects that have no slope.”

Seen from above, this project boasts an incredible Sarnafil PVC roof and at stadium level Sika EMSEAL roof joints around found throughout. This highlights the incredible synergies that Sika USA has to offer!