Due to the nature of construction, virtually every building is a unique, one-off design, including the design of complex mechanical and electrical systems and their control systems. The consequence of this sophistication and complexity is that high-performance buildings need to be carefully tuned and calibrated to ensure that their operation is as designed. The commissioning process has been shown to be invaluable in providing a high degree of quality assurance for buildings with sophisticated energy and conditioning systems and is now virtually standard practice for green building certification.
The world’s largest database of commissioning cost-benefit case studies was assembled by Dr. Evan Mills and his team at the Lawrence Berkeley National Lab in 2004 and updated in 2009. The results of the ensuing meta-analysis were eye opening. Of data gathered for 643 buildings across 26 states, the median normalized cost to deliver commissioning was $0.30/ft2for existing buildings and $1.16/ft2 for new construction projects. All told, according to Dr. Mills this represented an average of 0.4% of the overall construction cost. Through the rectification of the 10,000+ deficiencies discovered, a median energy savings of 13% was realized for the new construction projects and 16% for the existing buildings and payback times of 4.2 years and 1.1 years respectively. Furthermore, project teams that elected to implement a comprehensive commissioning process enjoyed nearly twice the overall median energy savings.
Perhaps the most compelling figures derived from Dr. Mills fall out of a simple extrapolation from the current stock of commercial buildings in the United States. Applying the median energy savings derived from the control group nationally results in a projected energy savings of $30 billion by 2030, the equivalent of approximately 340 megatons of CO2 each year. According to Dr. Mills, if each existing building in the U.S. were retro-commissioned every 5 years the commissioning industry would quickly swell to $4 billion per year, requiring an additional 1,500 – 25,000 full-time equivalent employees.
Rather than simply acting as a tool for the realization of energy savings, a well-executed building commissioning process may be more accurately described as a risk management strategy. It ensures that building owners have been delivered with a building that meets with their expectations within the specified budget and provides insurance for policy managers that their initiatives accurately meet targeted goals. Furthermore, the building commissioning process serves to detect and rectify issues that would eventually prove far more costly to the owner in the future from the standpoint of operation, maintenance, safety and unwanted litigation.
John Chyz is Managing Director of the Cross Creek Initiative, a non-profit/university joint venture seeking to drive research initiatives and pioneer solutions for sustainable built environments.
As an Engineer, Green Globes Assessor (GGA), ASHRAE Certified Commissioning Process Management Professional (CPMP) and AEE Certified Energy Auditor (CEA), John brings a comprehensive skill-set to the Cross Creek team and each individual client.
John is the instructor and course developer of the UF TREEO Introduction to Building Commissioning course being taught April 17, 2013 in Gainesville.
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