Milwaukee, Wisconsin

Fiserv Forum Hits Buzzer Beater With Sarnafil

With a roofing job as complex as the one on the Fiserv Forum, Langer Roofing & Sheet Metal Inc. of Milwaukee might have been tempted to “pass the buck.” The 730,000-square-foot arena, home to the NBA team the Milwaukee Bucks, is the cornerstone of a 30-acre district that is part of the largest development project in Milwaukee’s history. The unique roof structure of the arena alone --- including a barrel shape that gives into a gradual slope on one side and a more drastic pitch on the other – posed many challenges.

Fortunately, the roofing specification was for the Sarnafil adhered roofing system, which the Langer Roofing crew have been installing for years. Sarnafil adhered roofing systems deliver superior, watertight protection — the result of time-tested membranes and hot-air welded seams. They are best for low-sloped, uniquely shaped or pitched roof applications, such as the Fiserv Forum roof. “We are very experienced with Sarnafil systems, and the guys in the field like working with it,” remarked Jim Fleming, estimator at Langer Roofing. “Sarnafil is a great product,” added Kevin Higgs, senior project manager at Langer Roofing.

Fiserv Forum
Milwaukee, Wisconsin

Deer District LLC

Roofing Contractor
Langer Roofing & Sheet Metal Inc.
Milwaukee, Wisconsin

Roofing System
Adhered roof system, using Sarnafil G 410 80
mil EnergySmart Roof® membrane in white

Project Size
319,000 square feet

Ariel view of the Fiserv Arena
Fiserv Arena roof with Sika Sarnafil Membrane
A Tricky-Lay Up

One of the first challenges Langer Roofing faced was moving material around. “Due to the vast size of the deck and limited crane access, we had to use a cart system, six-wheeled manual vehicles to transport supplies across the nearly 600-foot-long roof structure,” Higgs explained. They also had to coordinate activities with other trades, as more than 4,000 workers from various trades were on the job site at the peak of the arena’s construction. “This required daily coordination with all the parties involved,” he stated.

Collaboration with Sika representatives also helped. “The Sika people were great about making sure the materials we needed were available,” Fleming said.

The roof assembly consisted of gypsum board secured to metal decking, covered with Sarnavap self-adhered vapor barrier, two layers of Sarnatherm polyisocyanurate insulation board, another layer of gypsum board, followed by the Sarnafil G 410 80 mil white PVC membrane. Because of the unusual shape and pitch of the roof, the crew and the carts were always required to be tied off. “We utilized a safety line system to keep up to 35 guys tied off in harnesses at the same time,” Higgs commented.

Setting insulation in the low-rise foam on a barrel roof also posed challenges. Fortunately, the Langer Roofing crew had mastered the use of ballast to hold the insulation in place until the low-rise set.

Avoiding Possible Blocks

A snow retention system using steel structure components at the base of each side of the barrel roof initially blocked access to the roof. “With the help of Mortenson Construction (the GC based in Minneapolis) we were able to jack up and suspend the snow retention system above the roof vertically, which allowed the crew and materials to pass underneath,” Fleming said. “As the roof was completed the rails were lowered back into place, ready for the Wisconsin winter to come.”

Speaking of the weather, most of the roofing system was installed during the cold, fall season. “We had to deal with typical Wisconsin fall weather like rain, flurries, and snow showers,” Higgs remarked. “The biggest challenge was keeping the deck dry and safe.”

Fiserv Arena building with roofing construction going on
Ariel view of the Fiserv Arena
Overhead Pass

Langer Roofing was also tasked with installing 700 square feet of perimeter gutters surrounding the north and south side of the building. This gutter system used Sarnafil’s G 476 SA waterproofing membrane applied to ¾ plywood, covered with insulation and Sarnafelt drainage layer with a 6” concrete topping creating the shape of the gutter. Specially fabricated brackets coated with PVC and a factory-applied target patch were utilized to secure the formwork. Each bracket was secured with screws and then welded securely to the base layer of G476 SA. The concrete gutter system also utilized a hydronic ice melting system.

“This was my first time using the Sarnafil waterproofing membrane, and I thought it was great,” Fleming stated. “It was really nice to work with such a quality product.”

Throughout each stage of the roofing and gutter installation, Langer Roofing followed a written quality control program outlining the steps each individual team member was responsible for, such as daily field samples, reports, photo surveys, and written site inspection reports. It was this attention to detail that earned Langer Roofing first place in the Low Slope Category of Sika Sarnafil’s 2018 Project of the Year competition.

A Winnings End Result

Since the Fiserv Forum opened in October of 2018, the Milwaukee Bucks ended an 18-year drought to win division titles in 2019 and 2020, reflecting the championship caliber of the roof. “The roof is doing very well and everyone is happy,” Fleming pointed out. “I would definitely use Sarnafil products again – they are great membranes and systems with no issues.”

Another Sarnafil assist for the win.