Commissioning is the process of ensuring that systems are designed, installed, functionally tested, and capable of being operated and maintained according to the owner’s operational needs. By utilizing building inspection and systems testing, commissioning can provide quality assurance and systematically improve the efficiency and operation of building energy systems (particularly HVAC and air-distribution systems). In addition to providing energy savings, commissioning often increases comfort for occupants. When the commissioning process is applied to an existing building that hasn’t been commissioned before, it’s called retrocommissioning (RCx).

As a comprehensive process rather than a set of prescriptive measures, RCx addresses a building’s underlying system-level deficiencies rather than isolated quick-fix problems. Its benefits include an energy-efficient building that is operated and maintained by a well-trained staff or service provider, a comfortable and safe working environment for the occupants, and energy savings that will persist over time. RCx can lower building operating costs in two ways: by reducing electric demand, energy consumption, and maintenance complaint calls and by increasing occupant comfort and equipment life. The Lawrence Berkeley National Laboratory (LBNL) 2009 report, Building Commissioning: A Golden Opportunity for Reducing Energy Costs and Greenhouse-Gas Emissions, remains among the most comprehensive to date on RCx. LBNL’s findings show that RCx is generally one of the most cost-effective means of reducing energy consumption in commercial buildings, with average whole-building energy savings of 16 percent. Median costs of commissioning were $0.30 per square foot with an associated simple payback period of 1.1 years for building owners.

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