The millions of passengers who pass through Denver International Airport each year no doubt have the usual list of things to review as they prepare for a flight: Checked baggage or carry-on? Buy some extra reading material or hope that the Wi-Fi on the plane is working? Grab
a quick bite before takeoff or take your chances with airline snacks?
DIA, which opened in 1995, is located 23 miles northeast of the metropolitan Denver area, on the high mountain desert prairie of Colorado. Its location showcases its spectacular design incorporating peaked tent-like elements on its roof, meant to evoke the nearby Rocky Mountains or Native American dwellings or both. Unfortunately, this location also places the airport smack in the middle of what is known as “Hail Alley”, the area east of the Rockies centered in Colorado, Nebraska and Wyoming. According to the Silver Spring, Md.- based National Weather Service, this area experiences an average of nine “hail days” a year. The reason this area gets so much hail is that the freezing point—the area of the atmosphere at 32 F or less—in the high plains is much closer to the ground. In other words, the hail doesn’t have time to thaw and melt before it hits the ground.
Not only are hail storms in this area relatively frequent, they also produce the largest hail in North America. The Rocky Mountain Insurance Information Association, Greenwood Village, Colo., says the area experiences three to four hailstorms a year categorized as “catastrophic”, causing at least $25 million in damage. Crops, commercial buildings, housing, automobiles and even livestock are at risk.
Statistically, more hail falls in June in Colorado than during any other month, and the storm that damaged DIA’s roof followed this pattern. In June 2001, the hailstorm swept over the airport. The storm was classified as “moderate” but still caused extensive damage to the flat roofs over Jeppesen Terminal and the passenger bridge. (It’s important to note that the storm did not damage the renowned tent roofs.) The airport’s original roof, non-reinforced PVC single-ply membrane, was “shredded” by the storm and needed extensive repair. Lovato and his team at CyberCon assessed the damage and recommended changes in the roofing materials that would stand up to Colorado’s climate. Lovato also oversaw the short-term emergency re- pairs to the roof and the installation of the new roof.
Under any circumstances, this would have been a challenging task. The fact that the work was being done at one of the busiest airports in the world made the challenge even more complex. The airport was the site of round-the-clock operations with ongoing public activity, meaning that noise and odor issues needed to be addressed. Hundreds of airplanes would be landing and taking off while the work was ongoing. And three months after the storm damaged the roof in Denver, terrorists attacked the World Trade Center, making security concerns paramount.
INSPECTION AND REROOFING
Lovato’s inspection of the hail damage revealed the extent of the problems with the airport roof. The original PVC membrane, installed in 1991, was showing signs of degradation and premature plasticizer loss prior to being pummeled by the June 2001 storm. The storm itself created concentric cracks at the point of hail impacts and, in most cases, the cracks ran completely through the membrane. In some instances, new cracks developed in the membranes that were not initially visible following the storm. The visible cracks were repaired immediately with EPDM primer and EPDM flashing tape until more extensive repairs could begin. Lovato notes that while nature caused the damage to DIA, nature was on the roofing team’s side when the repairs were being made: The reroofing project was performed during a drought, the driest in 50 years, minimizing worries about leaks into the terminal below and giving the construction teams almost endless sunny days to finish their job.
The initial examination of the roof also revealed that the existing polystyrene rigid insulation, ranging in thickness from 4 to 14 inches, was salvageable, representing significant savings. Although a single-ply, ballasted roof was considered and would have been an excellent choice in other locations, it was ruled out at the airport given that the original structure was not designed for the additional weight and substantial remediation at the roof edge perimeter possibly would have been required.
Lovato chose 90-mil black EPDM membrane for the new roof. “It’s the perfect roof for that facility. We wanted a roof that’s going to perform. EPDM survives the best out here, given our hailstorms,” he says. A single layer of 5/8-inch glass-faced gypsum board with a primed surface was installed over the existing polystyrene rigid insulation (secured with mechanical fasteners and metal plates) to provide a dense, hail-resistant substrate for the new membrane.In some areas adjacent to the airport’s clerestory windows, the membrane received much more solar radiation than other areas of the roof. When ambient temperatures exceeded 100 F, some melting of the polystyrene rigid insulation occurred. “That section of the roof was getting double reflection,” Lovato points out. To reduce the impact of this reflection, the roof was covered with a high-albedo white coating, which prevented any further damage to the top layer of the polystyrene rigid insulation board and also met the aesthetic requirements of the building.
Lovato’s observations about the durability of EPDM are backed up by field experience and controlled scientific testing. In 2005, the EPDM Roofing Association, Washington, D.C., commissioned a study of the impact of hail on various roofing membranes. The study, conducted by Jim D. Koontz & Associates Inc., Hobbs, N.M., showed EPDM outperforms all other available membranes in terms of hail resistance. As would be expected, 90-mil membrane offers the highest resistance against punctures. But even thinner 45-mil membranes were affected only when impacted by a 3-inch diameter ice ball at 133.2 feet per second, more than 90 mph—extreme conditions that would rarely be experienced even in the harshest climates.
Lovato travels frequently, meaning he can informally inspect the DIA roof at regular intervals as he walks through the airport. He’s confident the EPDM roof is holding up well against the Denver weather extremes, and he’s optimistic about the future. With justified pride, Lovato says, “I would expect that roof to last 30-plus years.”
90-mil Non-reinforced EPDM: Firestone Building Products
Gypsum Board: 5/8-inch DensDeck Prime from Georgia-Pacific
Plates and Concrete Fasteners: Firestone Building Products
White Elastomeric Coating: AcryliTop from Firestone Building Products
Existing Polystyrene: Dow
Not only does GacoElastomeric withstand ponded water, it remains flexible over time whereas acrylics become hard and brittle. It has higher solids than acrylics so more coating stays on the roof to provide better coverage and because of the unique chemistry it can be rained on after just two hours and won’t wash off the roof.
CoolStar products meet ENERGY STAR and California Title 24 requirements. CoolStar also qualifies for LEED points and meets NAHB National Green Building Standards.
CoolStar is designed to work with a wide range of roof systems, including built-up roofing, SBS, APP and self-adhering modified bitumen. It is extremely flexible and durable, because of the layering of high-quality reinforcements, heavy asphalt coating and highly reflective ceramic granules. This toughness combats the negative effects of natural expansion and contraction caused by heating, cooling, light and moisture. In addition, the brilliant white CoolStar surface is factory applied for hassle-free, one-step installation, which helps reduce labor costs.
GAF announced it has completed the acquisition of Quest Construction Products (QCP), a former division of Quest Specialty Chemicals and a supplier of fluid-applied roofing systems and roof-coating products in North America. The transaction, which also provides GAF with a strong presence in coating solutions for pavement and vertical surfaces, is expected to accelerate the robust growth of GAF’s commercial business.
QCP brings excellent brands and product lines to GAF including the Hydro-Stop family of liquid membrane products, the United Coatings line of coating solutions, and the StreetBond pavement coatings. The acquisition instantly gives GAF a position in a high-tech, environmentally friendly, and economically efficient segment of the commercial roofing business.
QCP’s strategically positioned geographic footprint and unique technical expertise in the field will provide GAF with additional solutions to bring to its customers. QCP’s products have gained rapid acceptance in the marketplace due largely to their reflectivity, ease of application, and energy-efficiency. These highly practical and effective products will complement GAF’s existing offerings of roofing technologies and commercial solar solutions.
“This acquisition combines a North American manufacturer and marketer of roofing products with a producer of fluid-applied solutions,” says Bob Tafaro, president and CEO of GAF. “We have acquired excellent brands and will provide an enhanced platform for their growth. QCP’s differentiated and innovative products will also boost our commercial business’s competitive advantage by offering a broader range of solutions to the market. We are empowering our contractors with the products they need to grow their businesses while strengthening our relationships with strategic building owners.”
“This acquisition demonstrates GAF’s ongoing commitment to growth and leadership in the commercial roofing industry. It is in keeping with the extraordinary investments we have made and continue to make to add capacity and gain share in commercial solutions such as insulation (ISO), TPO, and PVC single-ply membranes. We know that the QCP team will further enrich our culture of achievement, and we look forward to working together on a smooth integration.”
The Roof Coatings Manufacturers Association (RCMA) has launched its Speakers Bureau program to offer an educational presentation on reflective roof coatings. RCMA’s Speakers Bureau consists of several RCMA members with expertise on the topic who have volunteered to deliver presentations throughout the country.
This presentation, titled “Reflective Roof Coatings: Cool Stories,” is approximately one hour in length, and discusses the key benefits and the environmental importance of reflective roof coatings used on low-slope roof systems. The science behind reflective roof coatings is presented in an easy-to-understand format and real-world case studies are presented to illustrate the information presented. The presentation content is intended to enable attendees to:
- Understand the benefits that reflective roof coatings impart on low-slope roof systems.
- Recognize why reflective roofs are environmentally important and comprehend the science behind how reflective roofs save energy.
- Determine best practices for preparing a roof membrane and application methods for reflective roof coatings on low-slope roof systems.
- Identify payback, energy savings, and other non-quantifiable benefits by evaluating several real-world roof-reflectivity case studies.
RCMA is an approved continuing education provider with the American Institute of Architects (AIA) and RCI Inc. By attending the course, attendees qualify to earn 1 AIA General Learning Unit Hour (1 LU Hour) as part of AIA’s Continuing Education System or 1 RCI Continuing Education Hour (CEH).
Groups interested in offering this presentation at an upcoming meeting or event should contact RCMA Staff Associate Cecily Alfonsi to participate.
The AC Cool Roof Binder systems are based on Kynar Aquatec PVDF binders, developed by Arkema’s fluoropolymer group, and ENCOR Flex polymers from Arkema Coating Resins.
Currently three systems are available, allowing greater formulation flexibility across different applications:
- AC III Binder System – This system uses a Kynar Aquatec FMA-12 PVDF based topcoat and ENCOR Flex 187 all acrylic or ENCOR Flex 192 modified acrylic basecoat to provide the highest possible level of performance and durability. It is designed primarily for the most demanding cool roof coating applications.
- AC II Binder System – Utilizing a proprietary ENCOR Flex 187 all acrylic polymer or ENCOR Flex 192 modified acrylic latex, this base and topcoat system delivers excellent performance and meets ASTM D-6083, “Standard Specification for Liquid Applied Acrylic Coating Used in Roofing.”
- AC I Binder System – This ENCOR Flex 3186 styrene acrylic system provides a good mix of performance and value for less demanding applications.
David H. Rowe, a 28-year veteran of the metal roofing and wall panel industry, has been named vice president of sales for Roofinox America Inc., a supplier of quality Roofinox stainless steel coil, featuring mechanical properties and an architecturally distinctive matt finish for rollformed roofing panels.
Rowe joins Roofinox from Englert Inc., an American manufacturer of metal and aluminum roofing and wall panel coil, where he was director of product management responsible for the planning, development and introduction of all new products.
At Roofinox America, Rowe will be responsible for the direction and management of all sales and business development operations, including distribution and fabricator and installer relations for the Roofinox stainless steel product line; Roofinox Classic, a brush-rolled material designed for roofing and wall cladding; Roofinox Plus 0.0157, a ribbed surface material for smoother roofing results and economy; and Roofinox Terne-Coated with a tin-plated surface that develops a matt grey patina finish over time.
Rowe’s roots run deep in this market. He joined Englert in ’92 as a member of its sales force and since then held a variety of management positions in regional and national sales, project management and product development. During his career, he was responsible for the development and launch of more than 30 roofing and wall panel products and programs and several strategic partner alliances for related materials.
Among his responsibilities at Roofinox will be the development of alliances with distributors and metal wholesalers, leading manufacturers for roofing and wall-cladding panels and sheet metal workshops—all looking for Roofinox stainless steel’s combination of high longevity with a dull surface without artificial coating. This natural metal was developed in Europe especially for roofing and wall cladding.
Rowe also brings to Roofinox a proven track record for creating, developing and completing architectural detailing and material specifications for high-end commercial, institutional, and residential projects, and will be responsible for counseling, assisting and training customers, including designers, specifiers and roofing contractors.
He is well-known in the roofing fabrication and contracting industry and early on in his career was associated with Bass Associates, a Massachusetts-based contracting company, installing metal roofing and wall panels.