We live in a world that is constantly striving for improvement — better, faster, and more efficient. In recent years, that desire for “more efficient” has been supplemented with a movement toward other enhancements, broadly categorized as environmentally friendly, sustainable, or “green.” The green movement has gained considerable traction in the design of new buildings, from commercial properties and residential construction to industrial facilities and tension fabric aircraft hangars.
The hallmark of green building comes in the form of LEED (Leadership in Energy and Environmental Design) certification through the U.S. Green Building Council, which is achieved by meeting various design and operating criteria. But even for those building owners who choose not to go through the LEED process, greater energy efficiency and the subsequent reduction in operating expenses have become their highest priorities when erecting a new building.
Naturally Green Fabric
For hangars, storage structures, and other airport buildings, a certain level of energy efficiency is achieved simply by virtue of installing a building that utilizes a tension fabric roof. Both polyvinyl chloride (PVC) and polyethylene (PE) fabrics continue to improve in quality, and their natural properties make fabric roofs ideal for green-conscious building users.
The primary advantage of these structures from a sustainability standpoint is that fabric offers a high solar reflectance, keeping the roof cooler and reducing the heat island effect in the area by reflecting sunlight’s heat away from the building. Along with reflectance, tension fabric’s high thermal emittance also contributes to the roof absorbing less heat. During peak summer weather, these properties can combine to keep fabric roofs about 50 to 60 degrees cooler than roofs built with conventional materials, thereby reducing the need for temperature control measures inside the building.
Although fabric roofs are reflective, they also offer up to 12-percent translucency to allow natural light to permeate the structure. Direct sunlight offers about 10,000 footcandles of illumination, so even at 5 percent translucency, a fabric roof will let approximately 500 footcandles into a building on a sunny day — well above the recommended 75 to 100 footcandle guidelines for maintenance tasks inside an aircraft hangar.
Most hangars will still need artificial lights for nighttime work and to provide adequate illumination on stormy, overcast days, but during normal daylight hours, fabric roofs effectively eliminate the need for artificial lighting. By taking advantage of natural sunlight, tension fabric goes a long way toward reducing the electricity bill and making a building more energy efficient. And, for those interested in the accolades, these benefits also help to rapidly accumulate points on the path to LEED certification.
Though certain green benefits of tension fabric itself have always existed, other aspects of sustainability in tension fabric hangars have come along more recently because of an important engineering upgrade introduced to the market by Legacy Building Solutions — the use of structural steel beams rather than hollow-tube, open web-truss framing. This rigid-frame engineering concept allows much more design flexibility in customizing the size and alignment of a fabric building, while also allowing builders to incorporate additional features to make the structure more operationally and energy efficient.
Because the rigid frame is a more traditional architectural design that gives a fabric building significantly more strength, it’s become easier to add items like interior fabric liners and insulation to a structure’s roof and sidewalls. A certain temperature control barrier can be achieved simply by adding a liner to the main fabric skin. For even more effectiveness, the liner can be combined with insulation material to create a system with an insulation value of up to R-40. This level is capable of meeting almost all relevant energy codes in the country, providing significant heating and cooling cost savings.