Commissioning Process Important in LEEDing by Design

By George Bourassa, senior vice president and national director of commissioning services with the Fort Worth office of Carter & Burgess Inc.

A prerequisite for LEED certification, the commissioning process verifies that building systems are installed and operated at their maximum levels of efficiency.

These days so many experts are involved in building design and construction that no single firm or individual can perform oversight of the entire process. The commissioning provider fulfills this role, verifying that systems are installed properly and that the owner's design intent is realized through rigorous and extensive functional-performance testing of systems, interfaces and all possible sequences of operation. One reason to incorporate commissioning in project delivery is the desire to obtain certification through the U.S. Green Building Council's Leadership in Energy and Environmental Design program. LEED quantifies and certifies "green" buildings that are environmentally friendly and sustainable.

The Green Building Council first adopted the LEED standard in an attempt to eliminate "green washing"-making unsubstantiated claims about the energy efficiency or environmental friendliness of a building. All LEED-approved buildings achieve a high level of energy efficiency and limit their negative impact on the environment. A green building might use highly efficient power and lighting systems, recycled rainwater for irrigation, vegetation to shade sunny walls or recycled or renewable sources for building materials.

Fundamentally, commissioning involves three elements: record documentation, systems-functional-performance verification and operator training. Progress on all three should be ongoing throughout a project. Many owners consider commissioning the last step after construction and before occupancy, but that is a misconception. Ideally, commissioning should begin when a building is in the early schematic design phase.

The commissioning team operates as the owner's advocate throughout the design process, first working with the owner to understand and document the project requirements and then performing design reviews to ensure those requirements are reflected in the design solutions. The team also looks for possible conflicts related to system testing or maintenance.

During construction, the commissioning team continues to ensure the owner's requirements are realized. The team works closely with contractors to integrate commissioning activities into the overall construction schedule, to keep commissioning activities off the critical path and to carry out site inspections with a focus on systems operations and maintenance.

During functional performance testing and operator training, the commissioning team moves to the forefront. The team verifies the performance of building systems based on detailed test procedures, which they have developed, and determines the most efficient equipment settings. The team also supervises equipment for training operations staff and organizes warranty information. Ultimately, the team prepares extensive documentation on systems, including benchmarks for energy use and equipment efficiencies, seasonal operational issues, start-up and shutdown procedures, diagnostic tools and guidelines for energy accounting.

Commissioning costs can range widely depending on the scope of services provided. In general, the range is about .125 percent to 2.5 percent of construction costs.

Payback can be significant. Organizations that have researched commissioning claim that owners can achieve savings in operations of $4 over the first five years of occupancy as a direct result of every $1 invested in commissioning-an excellent return on investment.

Commissioning specialists recommend that owners not think of commissioning as ending at completion or warranty expiration. Owners benefit most when it is a seamless process that begins in the design phase and transitions into permanent facility management. "Continuous commissioning" efforts can also be adopted to monitor system operations and provide for "persistence" in maintaining targeted energy consumption levels and highly reliable system performance.

During construction, it is important to pay close attention to the reports submitted by the commissioning provider to ensure that the design intent isn't being compromised by value engineering decisions or change orders. Critical to the success of any commissioning process is the buy-in of all members of the project team. The commissioning team doesn't have a contractual relationship with the architect, engineers or contractors, so it is essential that the owner communicate from the beginning their commitment to the process.

Often the true measure of how well the commissioning process works is reflected in the level of cooperation among the architects, engineers, contractors and the commissioning provider. Most often, the commissioning provider needs to educate project team members on the benefits of commissioning and to lead the project team in understanding the owner's project requirements and maintaining a clear focus on achieving the quality component inherent in these requirements.