In the U.S., facilities consume 39 percent of the energy, 71 percent of the electricity and 30 percent of the country’s raw materials while producing 30 percent of its waste output. Legislation such as the Energy Independence and Security Act of 2007 (EISA) has been enacted to reduce the impact of facilities on the environment. Among its many provisions, EISA requires that federal facilities use green building rating systems to achieve a minimum certification level for 5 percent of all new buildings. The U.S. Air National Guard has taken a very aggressive stance on this issue, requiring that 100 percent of all new maintenance facilities achieve the minimum certification through the U.S. Green Building Council’s (USGBC) Leadership in Energy and Environmental Design (LEED) rating system. Additionally, all new administrative facilities must achieve the higher USGBC LEED Silver certification. By establishing these higher standards, the Air National Guard has demonstrated its commitment to sustainability and has created an environment of awareness for all parties involved in the building process.
Requiring that all new buildings attain a minimum level of LEED certification is an aggressive stance for a sustainable future; however, this requirement presents significant challenges for the design and construction communities, as well as facility stakeholders. Some challenges can be overcome; others are more daunting simply because of the type of facility being built or its location. There are also the limitations of LEED itself to consider. The LEED rating system is based on a two-story office building in a downtown, urban environment. Naturally, if a proposed new building fits these criteria, the potential for that particular project to earn LEED credits is greatly enhanced. However, new buildings being built on military installations do not fit this model and, as a result, opportunities to earn LEED® credits are more limited, more challenging and in some instances not feasible in this scenario.
Going Green at Fort Smith
The recently-completed A-10 Aircraft Maintenance Facility for the Arkansas Air National Guard (ANG) 188th Fighter Wing at Fort Smith, Ark., became the first ANG facility to earn USGBC recognition when it was awarded LEED Silver certification. The facility was a performance-based design-build project required to achieve a minimum LEED Certified rating, or a minimum of 28 points under the LEED for New Construction (NC) version 2.2 rating system.
The facility consists of three individual hangar bays that are each approximately 8,500-ft2 in size. The facility supports inspection, repair and servicing for corrosion control, fuel cell maintenance and weapons loading training for the A-10 aircraft. The facility also includes administrative areas such as offices, a classroom, a conference room, a break room, a locker room with showers and restrooms.
Given the location and industrial nature of the facility, the opportunity to achieve LEED credits was extremely challenging. Because the certification team recognized the innate challenges of achieving certain LEED credits, a plan was formulated to ensure certification would be achieved. The team recognized the area that presented the greatest challenge to the project was minimum energy efficiency in an industrial facility with large open bays. In addition, points associated with community connectivity, public transportation access, ride-sharing and van pools were other areas that would simply not be an option for the project. To compensate for these “unattainable” credits, exemplary performance points were pursued in other areas. Exemplary performance points are awarded by going above and beyond the maximum required level to achieve certain credits. The summary below highlights the credits that presented the greatest challenges to the certification team and the credits where exemplary performance was pursued and achieved:
- Energy and Atmosphere (Energy Efficiency). The LEED NC rating system requires a minimum energy efficiency to achieve certification. This is evident by requiring a minimum of two points to be achieved under Energy and Atmosphere Credit 1 – Optimize Energy Performance, which translates to a 14 percent energy cost savings. Energy efficiency is determined by calculating a baseline case as defined by ASHRAE/IESNA 90.1 – 2004 and then designing a system that achieves an energy cost savings below that baseline case. The challenge in achieving the required energy efficiency for facilities like aircraft hangars is that large open bays require ventilation per OSHA and industrial ventilation requirements. Ventilating large open bays requires large amounts of energy, which works against energy efficiency and is not accounted for in the baseline case. To counteract this energy inefficiency, energy recovery units were used to make the ventilation of the hangar bays a more energy-efficient process. This allowed for the energy required for ventilation to be counteracted. As a result, a 20.4 percent energy cost savings was realized, which translated into achieving three points under Energy and Atmosphere Credit 1.
- Water Conservation. The process of calculating water efficiency for LEED is similar to that of calculating energy efficiency. A baseline case is determined according to the Energy Policy Act of 1992. The fixtures installed in the facility must achieve a reduction in water use below the calculated baseline. There are three points that can be achieved under Water Efficiency Credit 3 – Water Use Reduction. The first point is achieved by reducing potable water usage in the facility by 20 percent. Two additional points are available for reaching the 30 percent and 40 percent thresholds, with 40 percent being considered exemplary performance. This project was able to achieve exemplary performance by achieving a 50.8 percent water use reduction through the use of low-flow fixtures and waterless urinals.
- Construction Waste Management. Construction waste management was an area where the certification team made a conscious effort to maximize the opportunity for points. A construction waste management plan was created by the contractor and implemented by educating all subcontractors as to what was expected of everyone working on the project site. All waste generated on the site was analyzed to determine if it could be diverted from landfill. For example:
- A portion of existing concrete apron required to be demolished was crushed and used as fill on the site.
- An existing aircraft hangar on the site was required to be demolished so the new facility could be built. In lieu of demolition, the hangar was dismantled and re-assembled off-site for reuse.
- All waste generated on site was separated into items that could be recycled and those that could not. As a result, only a very small portion of the waste was not recycled.
- Regional Materials. Regional materials was another area where the certification team concentrated on achieving the maximum amount of points available. Materials are considered “regional” when they are harvested, recovered, or manufactured within 500-mi of the project site. The intent behind this credit is to reduce fuel consumption and emissions associated with shipping items to the site. There are three points that can be achieved under Materials and Resources Credit 5 – Regional Materials. The first point is achieved by purchasing a minimum of 10 percent regional materials. Two additional points are available for reaching the 20 percent and 40 percent thresholds, with 40 percent being considered exemplary performance. This project was able to achieve exemplary performance by purchasing 41.4 percent regional materials.
The requirement set forth for the project was to achieve a minimum of 26 points for a certification level of LEED Certified. Through the strategies illustrated above, the certification team was able to go beyond the prerequisite requirements and achieve 35 points. This not only exceeded the minimum points required, but also enabled the project to earn a LEED Silver certification level and the distinction of being the first facility to earn a LEED certification of any kind for the Air National Guard. By achieving this milestone, the 188th Fighter Wing and Air National Guard has shown its commitment to providing sustainable facilities that enhance the work setting for personnel, reduce impact on the environment and contribute to the mission. Additionally, through the performance-based design-build process and a strong emphasis on LEED certification, this project was awarded a Citation Award for Concept Design from the United States Air Force 2009 Design Awards Program.
With the sustainability requirements the Air National Guard has implemented, we can look forward to many more Air National Guard projects achieving LEED certification. While the prospect of many more LEED certified projects for the Air National Guard will undoubtedly add to a brighter future for the built environment, the LEED Silver-certified Composite A-10 Maintenance Facility for the 188th Fighter Wing at the Arkansas Air National Guard will always have its unique place in ANG history as the first.