Leadership in Energy and Environmental Design, commonly referred to as LEED, was instituted in 1998 by the U.S. Green Building Council and is now a governing body that sets standards for environmentally conscious design. In order to produce a facility that is LEED certified, specific guidelines within the LEED rating system must be followed. The rating system assigns point values to initiatives within the design that fall into the following six categories: Sustainable Sites, Water Efficiency, Energy and Atmosphere, Materials and Resources, Indoor Environmental Quality, and Innovation in Design. The point values add up to various levels of LEED certification. A LEED Certified building follows the ratings guidelines and has between 26 and 32 points. LEED Silver certification has between 33-38 points, Gold is between 39-51 points, and the highest level, LEED Platinum, is for facilities with 52 to 69 points. By following the LEED process, the U.S. Green Building council provides a metric by which buildings can be defined as “green.”

Movements toward green building practice, particularly with LEED certification, are rapidly growing, and have been in recent years. With four levels of LEED certification (LEED Certified, Silver, Gold, and Platinum), LEED practice has become more adoptable and is now touted by governmental agencies. Some agencies have LEED mandates that are dictated to organizations that wish to do business with them. Because forensic facilities are closely related to governmental agencies, LEED has become a part of forensic facilities at all levels. Why have these agencies chosen to embrace LEED? With the increasing cost of fossil fuels and costs associated with owning, operating, and maintaining buildings, forensic facilities designed by LEED standards are appealing because of the long-term cost benefits. Although some see LEED as a trend, those that have witnessed the benefits firsthand view LEED as an evolving standard.

The Scottsdale Forensic Facility was one of the earliest forensic facilities to adopt LEED strategies. Located in the eastern part of Maricopa County, Arizona, and adjacent to Phoenix, the Scottsdale Forensic Facility will house a full-service crime laboratory as well as a large evidence warehouse. Scheduled for completion in 2009, the facility will be over 53,000 gsf with projected construction costs at $10.5 million. In this article, the green strategies used at the Scottsdale Forensic Facility are explored to spark consideration on how to implement LEED standards in your facility.

The city of Scottsdale has a long-standing reputation for embracing green culture. In 1998, Scottsdale established the first green building program in the state of Arizona, geared specifically towards residential construction. Since then, the city has continued their strong commitment to green. In 2005, they were the first city in the U.S. to adopt a Gold building policy for new and renovated city buildings. Adding to their green reputation, in 2009 the city will have a LEED forensic facility. Green has become a standard in Scottsdale.

Forensic facilities have a number of unique characteristics that differentiate them from other building types. As in all laboratory buildings, the safety and security of employees is paramount. However, unique to a forensic facility, the safety and security of evidence is equally as important. Forensic facilities have many laboratory functions that are similar in nature to other laboratory building types, but they also have a number of special laboratory types, such as firearms, which present new challenges to the building support and construction. Also, forensic facilities need to accommodate future functions and require flexible design of laboratory spaces as well as the infrastructure supporting those spaces. Many of these unique characteristics may seem antithetical to LEED practice, but for Scottsdale, these challenges were met head on to achieve a green building.

LEED Scottsdale Forensic Facility
The 53,000 gsf LEED Scottsdale Forensic Facility will house a full-service crime lab and large evidence warehouse.

As in most laboratory facilities, energy consumption is a major issue. All forensic laboratories have one-pass air systems where conditioned air for the lab is used once and then exhausted outside the building. By using variable supply air delivery, air distributed to the laboratory areas is matched with the actual space load to reduce fan energy and the required reheat energy. On the exhaust side, a manifolded laboratory exhaust system with common plenum was utilized in Scottsdale to track actual exhaust demands of the building. Fans run only when needed to minimize required fan energy. An energy recovery system was also used to capture heat that would be otherwise discharged out through the exhaust system to precondition the outside air entering the facility. With this approach at Scottsdale, air volumes introduced to the laboratory spaces were minimized and captured the heat energy within the reduced airflow for use back in the building. This approach at Scottsdale leads to a building system that performs 18% better than the ASHRAE 90.1 baseline. This allows building owners a 7.5% savings, amounting to around $15,100 saved annually.

CO2 monitoring is another technique for saving energy in laboratory exhaust. Without knowing the exact CO2 content of the air in laboratories, air change rates have been established to ensure the safety of employees in the laboratory. Are the same air changes required at all times in a laboratory? With the CO2 monitoring system used in Scottsdale, the CO2 in the air is monitored in the laboratory and is automatically dialed back or increased as required. The upfront cost of the monitoring system is returned in savings of lower average air exchange rates than dictated without a CO2 monitoring system. The constant monitoring also improves the air quality of the laboratory while still saving energy costs.

Another way to save energy in a forensic facility is to provide more controllable user situations within the laboratory. Individual task lighting to supplement daylight as well as items such as point exhaust in lieu of large fume hoods, serve users just as well while decreasing energy consumption. Small changes can add up to noticeable savings. At the Scottsdale facility, the users agreed only one sink per laboratory needed both hot and cold water. By providing hot water at a limited number of laboratory sinks, smaller point-of-use water heater devices were utilized locally instead of a whole house water heating system. A whole house system includes not only the water heater itself and the associated space in the mechanical room to allocate the central equipment, but also a substantial amount of piping to convey the water to the necessary distribution points. This small change saves with initial equipment costs and continues energy savings over the life of the facility.

The largest culprit for energy consumption in a forensic laboratory is often the fume hoods. Keep abreast of new technology and work with users to choose alternative units because fume hood selection has a large impact on energy consumption of the facility. Some new technology and alternative units may require additional training and adaptation, but that does not compare to the substantial savings in energy costs. The fume hoods chosen for the Scottsdale facility was not new technology. By restricting the sash opening, the amount of conditioned air is greatly reduced. However, this non-traditional restricted sash opening requires user buy-in and compliance. A forensic laboratory can be an ideal circumstance for such restricted sash openings, as many of the processes in a forensic laboratory are not unduly hampered by these restrictions.

Although many of these energy saving opportunities are also applicable in other laboratory types, many fit well within the forensic framework. Keep in mind, some energy saving opportunities for a facility in Scottsdale, Arizona might not equal the same savings in another northern location. Although LEED is now a driving force in public facilities, the considerations of green building practices and applying LEED to forensic buildings must be considered on an individual basis, choosing point categories and strategies that work well based on the science involved in a particular facility as well as location of the structure.

As government owned facilities continue to push the practice of green building and LEED forward, we will continue to see more and more LEED certificated forensic facilities. With careful and creative consideration, forensic laboratories can achieve certification and become examples of good LEED building practice for other similar building types. The Scottsdale Forensic Facility is helping evolve the LEED trend to an industry standard.

Susan Halla is a Project Leader with Crime Lab Design, which provides full architectural and engineering services for forensic and medical examiner facilities worldwide.

Gabriela Kleiman, LEED AP, is an Associate and Forensic Laboratory Planner with Crime Lab Design.

Nicholas Raab, PE, is a Principal and Project Engineer with Crime Lab Design.