Flying High: Metal building system provides world’s first LEED Platinum aircraft hangar
by Jonathan McGaha | November 30, 2009 12:00 am
Metal building systems are popular choices for airport hangars because they are cost-effective and can offer clear spans to suit any size aircraft. Hangar 25 demonstrates that they are also sustainable. Steel is used for the primary structural members, and it is the most recycled and recyclable building material in the world. The hangar gained valuable LEED points for its recycled content and recycled steel was a large part of that.
The structural members in a metal building system are also custom engineered to handle the specific load needs for the building. This optimizes the steel used in the building and keeps costs down. In this case, that also meant designing a structure that could handle a 225 kW photovoltaic system on the roof. This solar array has more than 1,500 PV panels, producing 110 percent of the power needed to operate the facility.
It is expected to produce more than 400,000 kWh of energy per year. The PV panels are mounted to the standard R-panel roof on a rack system that attaches to the purlins.
The roof itself is considered a cool roof, with a solar reflectance of 0.70, an infrared emittance of 0.85 and a solar reflective index of 85.
The electricity savings from the solar array are significant. The building has operating expenses that are approximately two cents per square foot, compared to a traditional hangar that operates at about 20 cents per square foot. All of the equipment for the hangar, including rechargeable tractors, forklifts and tugs, run off the electricity produced by the solar grid.
When aircraft receive maintenance, the power
to keep all the systems running comes from the solar array. Using the solar power is not only cost-effective, but it also does away with fumes and odors from the diesel and jet fuel that would ordinarily be required. An added benefit of the PV system is the shading it provides to the roof. This helps to keep the cooling costs down and, along with the highly reflective white metal roof panels, reduces the heat island
effect of the building.
Six large metal fans hang from the steel frame of the building and provide a low-cost system for circulating air. The large volume, slow-moving fans help to maintain high air quality and keep the hangar cool in the summer and warm in the winter. Additionally, when a plane comes in fresh from a flight they can blow away condensation quickly.
Daylighting is also a popular energy saving feature in new buildings, and the ease with which a metal building system can handle this is evident in Hangar 25. There are more than 100 translucent panels in the metal roof, keeping lighting costs down and creating a better work environment. More than 95 percent of the regularly used areas of the facility, including the office space, receive natural daylight.
The versatility of the building is manifested in the combination of the office and hangar space, allowing the nose of an aircraft to pierce the typical office-hangar line. This design allows for the first and second floor offices to be situated on both front corners of a building, while utilizing a fully glazed translucent front entryway, showcasing views of an aircraft. There is also a steel bridge across the foyer that allows occupants to cross to either side of the offices and provides excellent views of the hangar operations.
The concrete floor of the hangar incorporates a unique, diamond-polished surface. In many maintenance hangars the floors often have a coating with epoxy and other potentially harmful contaminants that need to be resurfaced every few years. The natural concrete floor of Hangar 25 was polished to a bright finish using a diamond-bladed polisher.
The final product is a chemical-free concrete floor that is estimated to last at least 20 years, and those who work here won’t have to worry about toxic compounds. Another benefit of the polished floor is the high reflectivity, which increases the impact of daylighting.
Other sustainable features include low-flow plumbing fixtures, natural landscaping and a special water mist fire suppression system. Hangar 25 at the Bob Hope Airport is an excellent example of how metal building systems can incorporate the benefits of sustainable designs.
Jay D. Johnson is the director of architectural services for the Cleveland-based Metal Building Manufacturers Association and a LEED Accredited Professional.
Source URL: https://www.metalarchitecture.com/projects/flying-high-metal-building-system-provides-worlds-first-leed-platinum-aircraft-hangar/