The Carver-Hawkeye Arena at the University of Iowa’s Iowa City campus has been the site of many winning performances, including that of its roof. The 48-mil, mechanically attached Sarnafil roof had done its job admirably for 25 years, until an unusually severe storm damaged parts of the roof in the spring of 2006. The aging membrane continues to perform today in its new, recycled rendition as roofing walkway membranes. Meanwhile, its Sarnafil replacement roof continues the legacy of being a high-performance roofing membrane.

The Carver-Hawkeye Arena, which opened in early 1983, is considered to be one of the 15 largest university-owned facilities in the nation, and it serves as Iowa’s home basketball arena. The arena seats 15,500 for basketball and also is host to numerous concerts and sports camps, as well as commencements and other events.

The arena’s original Sarnafil roof was installed in 1981, and because of its advancing age, Jeff Hayes, engineer at the University of Iowa, had been planning to gradually phase in a new roofing system. That plan changed on April 13, 2006.

“On that day we had a very severe storm with hail and tornadoes,” Hayes stated. “As might be expected, this did cause some damage to the roof.” Hayes suddenly found himself facing a very narrow time frame in which to replace the roof before the basketball season began in the fall.

University Chooses Energy-Saving Roof

The University of Iowa retained Benchmark Inc. of Cedar Rapids, Iowa, to perform roofing consultant services for the project. After evaluating various roofing options, Benchmark narrowed its recommendations down to the Sarnafil system and one other single-ply roof. According to Tom Irvine, Benchmarks’ senior consultant and project manager, the recommendation was based on Benchmark’s favorable experience with Sarnafil roofs and the longevity of the arena’s original Sarnafil roof system.

In the end, the Sarnafil EnergySmart Roof 60 mil S327 mechanically attached system was selected for several reasons. One was that the new membrane could be effectively welded to the old Sarnafil membrane during the anticipated phasing of the roof installation. Another was that the roofing contractor, CEI Roofing Texas of Dallas, thought Sika Sarnafil’s bid was very well presented.

“This was the best bid package I’ve ever seen,” CEI President Byron Warnick stated. “It was very comprehensive and listed every item we would need on the roof.”

Recycling the Old Membrane

Sarnafil's Sarnatred Walkway, shown, is manufactured using recycled roofing material.

Prior to the start of construction, Sika Sarnafil technical sales representative Ken Baragary came up with a proposal for the old membrane. Instead of sending it to a landfill, why not recycle it for use in a new Sika Sarnafil product?

Hayes liked the idea. “The University is always looking for opportunities to recycle materials that would otherwise end up in the landfill,” he said.

Warnick stated that while recycling the membrane might add some steps to the installation of the new roof (the contractor had to cut and roll up the old membrane as they removed it, for instance), CEI Roofing was still enthusiastic about the idea. “This was a great idea from Sika Sarnafil. They really are the pioneers in recycling old roofing membranes and we found this very exciting,” he explained.

While the new Sarnafil roof was being installed, the old roof was being rolled up and sent to BES Industrial Services Inc. of Cedar Rapids, Iowa, where the membrane was ground up. However, despite the age and service of the 25-year-old roof material, it still proved to be a resilient player.

“This was pretty tough stuff — a lot tougher than any other PVC material we’ve ever processed,” said Todd Pender, plant manager at BES Industrial. “Most plastics, you hit and they shatter, but this one was flexible and in great shape—especially for having been on a roof for 25 years!”

Meeting + Exceeding Scheduling Goals

CEI Roofing had to not only be skilled, but also fast. “We only had two months in which to do the job, because the work had to be completed before basketball season,” Warnick explained. “Fortunately, Benchmark did a good job of writing the bidding documents, which allowed us to proceed without being interrupted by changes or delays.”

Due to the short construction window, it was anticipated that this project would not be completed before winter, thus requiring Phase 2 work to be completed in the spring of 2007. Due to CEI’s aggressive scheduling, the phased approach was not required. CEI employees were confident that they could complete the entire project in one phase, before cold weather arrived—and they were right.

“We did not think any company could complete the entire project before cold weather arrived, which is why this project was set up for two phases,” said Hayes. “The fact that CEI Roofing was able to do this in one phase is a testament to their proficiency and professionalism.”

CEI Roofing put 20 men on the roof for the first month, and a crew of 10 on the roof for the second month. Both crews worked seven days a week, except for the four days when there were home football games.

The crew began by removing the old membrane and replacing the insulation around the outer edges of the roof. Most of the remaining insulation, however, was in very good shape and could be reused. DensDeck was mechanically fastened over the insulation and the Sarnafil EnergySmart Roof membrane was then installed.

The roof is supported by exposed Cor-Ten steel trusses, so CEI used copper brown colored Sarnafil flashing membrane on truss column bases. “That way the flashings blend in with the columns when looking up from the ground level and any membrane seen from the ground up is copper brown colored,” Warnick said. “It looks beautiful.”

A Repeat Triumph

Both the new and old Sarnafil roofs scored high praise among those involved with the project. “My experience to date with Sika Sarnafil has definitely met or exceeded all expectations we had for them,” said Hayes. Irvine noted, “Benchmark is impressed with the finished roof system, and the efficiency and workmanship exhibited by CEI Roofing.”

Warnick was especially pleased with the recycling aspect of the project. “Now that we’ve handled one recycling project I think we will look into this for other jobs,” he said. “I think this will be something that owners will want to be a part of.”

“It’s a win-win situation for everyone,” Hayes said.

Carver-Hawkeye Arena, Iowa City, Iowa

Owner: University Of Iowa
Consultant: Benchmark Inc., Cedar Rapids, Iowa
Roofing Contractor: CEI Roofing Texas, LLC, Dallas
Roofing System: Sika Sarnafil mechanically attached roof system, using white Sarnafil 60 mil S327 EnergySmart Roof membrane
Project Size: 158,000 square feet


For more information about Sika Sarnafil, call 800-451-2504 or visit www.sikacorp.com.