Wings over the Rockies Air & Space Museum, Denver
RETROFIT TEAM
ARCHITECT: AH Architecture, (720) 932-8604
ROOFING CONTRACTOR: Colorado Custom Metal Inc., (303) 920-0169
CRANE OPERATOR: Winslow Crane Service Co.
MATERIALS
The existing 20-gauge corrugated metal roof on this large airplane hangar had reached the end of its useful life—but had performed well since it was installed in 1938.
Colorado Custom Metal proposed leaving the existing corrugated metal roof in place and retrofitting it with a new lightweight roof system. This approach would allow the museum to remain open while the new roof system was constructed.
Mill-finished Galvalume material was selected for the standing-seam panels to preserve the look of the old hangar and meet the criteria of Denver’s Historical Landmark Preservation Commission. Colorado Custom Metal fabricated 25,000 linear feet of 6-inch-high Z Purlins from 16-gauge GI steel in the firm’s metal shop. Installers attached the Z Purlins through the existing corrugated deck and into the main frame of the building, which transferred the load of the new roof system and raised the new fastening point 6 inches higher.
Next, the crew laid 6 inches of new insulation nested tightly between the newly secured Z Purlins; the crew used two layers of 3-inch foil-faced isocyanate insulation board, providing the building with an added R-value of 38. Finally, installers enclosed the insulation and Z Purlins with a high-temperature ice and water shield membrane.
Colorado Custom Metal manufactured the 308-foot-long panels in four separate lengths. The crew designed a custom expansion joint end-lap-detail to attach the panels together, making them span the full length of the barrel.
Winslow Crane Service hoisted the panels and New Tech Machinery’s panel forming machine up to the roof level, suspending it a few inches off the roof deck where 92,400 square feet of roofing panel was manufactured, utilizing the 18-inch-wide, 1 3/4-inch snap-seam profile. The panels were curved around the radius of the barrel as each one was installed.
Fabral supplied the 24-inch-wide, 24-gauge, satin-finished Galvalume roofing coils to make the standing-seam panels, as well as more than 300 flat sheets to custom-fabricate the flashings, trim and components for the project.
Once the new roof was installed, the project consultant observed heavy snow sliding off the new satin-finished metal roof panels in greater volume than the pre-existing corrugated roof panels. To control rooftop avalanche conditions, S-5! designed and engineered the ColorGard snow-retention system. Manufactured from high-tensile, certified aluminum and tested for load-to-failure results, ColorGard reduces the risks associated with rooftop avalanches and complements the look of the roof. ColorGard also is designed to last the life of the roof.
BASE-METAL SUPPLIER: Fabral
ROLLFORMING: New Tech Machinery
SNOW-RETENTION MANUFACTURER: S-5!
THE RETROFIT
Transferred from the U.S. Air Force to a group of volunteers in 1994, Wings Over the Rockies Air & Space Museum is located in Hangar 1 of the former Lowry Air Force Base. The museum boasts more than 182,000 square feet of iconic aircraft, space vehicles, artifacts, military uniforms and more. Visitors can experience flight simulators, discover various educational programs and participate in dozens of museum-sponsored events.
PHOTOS: S-5!