Property management companies are well familiarized with the activities and responsibilities that come with building ownership: design, permits, construction, maintenance, and occasional demolitions or major renovations. However, the commissioning process is also important, but frequently overlooked. Many buildings have never been commissioned, which leads to poor equipment performance and higher ownership costs. Occupant comfort and health can also be affected negatively.
What is Commissioning?
In simple terms, commissioning (abbreviated as Cx) is a process that keeps buildings under optimal operating conditions. This is accomplished by comparing actual operation with a series of predefined metrics, and making the necessary corrections when a building system falls short. To make commissioning possible, there are two important requirements:
- Establish a performance baseline, to serve as a reference for building systems. You cannot evaluate building performance if there are no metrics for comparison.
- Define how performance will be reported. Communication between consultants, designers, contractors and maintenance departments is much simpler when documentation is standardized.
Based on when commissioning is carried out, and the existing building conditions at that time, different names are used when referring to it:
- When the term commissioning (Cx) is used by itself, it generally applies to new buildings, and is carried out during design and construction. Typically, the most intense commissioning work is carried out after the building is completed, but before starting operations.
- Retrocommissioning (RCx) applies for existing buildings that had never been commissioned before. It also applies if a building was commissioned long ago, but there was no follow-up work and performance declined.
- Recommissioning (ReCx) applies for buildings that are commissioned at regular intervals. Normally, this process is simpler than new building commissioning or retrocommissioning.
Commissioning as an Investment in Your Property
Commissioning tends to have a very high return on investment, and a payback period of less than one year is feasible. This is because commissioning consists mostly on inspection, analysis, control adjustments and low-cost reparations, and there are no major capital expenses.
Want to ensure maximum facility performance with minimum operation cost?
Fixing performance issues during the design phase of a project is cheaper than modifying completed work, and proactive maintenance has a lower cost than solving problems after their occur. Commissioning can be considered an investment, given its long-term benefit in terms of building performance. Commissioning also makes energy efficiency measures more valuable, preventing a decrease in energy savings over time.
With modern communication technologies and the Internet of Things (IoT), the concept of monitoring-based commissioning (MBCx) becomes possible. Unlike normal recommissioning, where building issues are detected and fixed at regular intervals, MBCx detects issues in real time or even proactively. This allows quick action, and drops in performance are corrected when their impact is still small.
How Performance Testing is Carried Out
The testing procedure applied during commissioning can be broken down into pre-functional and functional performance testing.
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PERFORMANCE TESTING |
DESCRIPTION |
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Pre-functional |
Building equipment is tested separately for correct location, installation procedure and labeling. The procedure also includes control systems and software. |
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Functional |
Complete building systems are tested for overall performance and adequate interaction. Testing is carried out under various conditions that are possible during normal operation and during emergencies. |
Main Benefits of Commissioning
Commissioning not only reduces the energy consumption of building systems; it also prevents expensive breakdowns and creates better indoor conditions for occupants. Also consider that indoor comfort and air quality lead to improved productivity in business settings.
The following table summarizes the main benefits achieved with commissioning:
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BENEFIT |
DESCRIPTION |
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1) Optimization and efficiency |
Building systems can sustain the operating conditions as specified in design documents, and ownership costs are kept low. In a study with 643 buildings, the Lawrence Berkeley National Laboratory determined that commissioning reduces energy expenses by 16% in existing buildings, and 13% in new buildings (on average). |
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2) Improved comfort and indoor air quality |
Occupants feel better, in terms of both physical health and mood. For businesses, this leads to increased productivity and profit margins. Some examples of performance issues that affect comfort are temperature extremes, humidity extremes, excessive airspeed from ventilation, unpleasant odors and noise. |
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3) Longer building and equipment service life |
Building reparations and equipment replacements are expensive and disruptive. With commissioning, their frequency is reduced drastically. |
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4) Getting to know buildings better |
Since commissioning involves documentation, it provides a clear snapshot of operating conditions. Maintenance can be programmed more effectively, and problem areas are kept under closer watch. Troubleshooting also becomes much simpler. |
Reactive maintenance has been the traditional approach in buildings - fixing issues once they occur. However, this can quickly drain maintenance budgets, and minor issues go undetected. Commissioning provides financial benefits in general, driving up profit margins while reducing O&M expenses.
Is Commissioning Mandatory in New York City?
Although commissioning is recommended even when it is optional, there are cases where it is mandated by NYC law.
- Commissioning is mandated by the NYC Energy Conservation Code in buildings that exceed certain equipment capacity thresholds.
- All buildings covered by Local Law 87 of the Greener, Greater Buildings Plan must be recommissioned at intervals no longer than 10 years.
When a building experiences a gradual drop in performance and rising costs, which cannot be attributed to a specific building system, commissioning is highly recommended. If you are unsure if your property is subject to mandatory commissioning according to NYC laws, asking a qualified engineering consultant is the best solution.
The first step to save energy is knowing how your building uses it. NY Engineers can analyze your consumption with energy modeling: call or write at info@ny-engineers.com.
