People reviewing buildging plans as part of the commissioning or retrocommissioning process

Existing Building Commissioning

Existing building commissioning (EBCx) is a process by which the energy performance of an existing (as opposed to newly-constructed) building’s systems and operations is tested for inefficiencies and improved through repairs, tuning or the installation of new equipment. The EBCx process also follows up any improvements with testing to verify that the building is actually performing better. This makes the building more comfortable and energy-efficient, which saves energy and lowers operating costs.

We are a leader in the commissioning field, offering best-practice and customized services for EBCx (also known as retrocommissioning), including distinct variations to the traditional process that leverage different types of powerful technology, including Monitoring-Based Commissioning (MBCx) and incorporating Energy Information Systems (EIS).


There are roughly 80 billion square feet of existing commercial building space in the U.S. To this, add the facts that the majority of these buildings: were constructed with equipment that is inefficient by modern standards; were likely not verified to be constructed to the designed level of efficiency; have likely not relied on ongoing testing and strategic maintenance to prevent the degradation of equipment performance and energy efficiency that occurs naturally over time.

Poor energy performance doesn’t simply raise the number on a utility bill—it can decrease property value, tenant retention, building comfort and indoor air quality. There is immense opportunity to lower energy consumption in existing commercial buildings and, as a result, decrease overall electricity demand, save building owners money and make buildings more comfortable for occupants.

Typical Barriers

The fact that it remains a mostly untapped opportunity speaks to the barriers utilities face when trying to bring EBCx to their customers:

  • Typical retrofit programs with “custom” offerings don’t capture operational energy savings opportunities and often fail to ensure new equipment is integrated into the building’s operations strategy in the most efficient manner
  • There are often not enough trained engineers in the service area to deliver an investment-grade audit with reliable energy savings estimates
  • Cost-effectively applying the EBCx process to buildings under 100,000 square feet, which represent the vast majority of commercial customers, is more difficult than doing so in the larger buildings that are typical EBCx candidates
  • The customized nature of EBCx makes internal management of a large-scale program difficult: “How do we manage a large pool of service providers and custom projects conducted across many divergent building types, systems and measures in a way that yields consistent, reliable results?”

Unfortunately, many third-party implementers of energy efficiency programs don’t adequately address these concerns, instead focusing only on a small number of the largest buildings in a territory or offering semi-prescriptive programs that lack comprehensive sets of measures and produce less reliable energy savings claims.

Our Solutions

At PECI, our deep history in the commissioning industry allows us to approach EBCx with a clearer focus on large-scale effectiveness and reliability. We built a time-tested EBCx toolkit that includes everything required to launch a program with confidence: processes, report templates, forms, calculators and trade ally training. We’ve independently examined dozens of EIS tools and know which can bring the most value to an analytics-enabled EBCx program based on the specific needs of our clients. We leverage the power of EIS to accelerate screening, better manage persistence and improve the sales cycle with virtual auditing.

We offer three distinct types of EBCx programs:

  • Traditional EBCx. Our programs rely on seeing each building as a whole. Trade allies in our programs are trained to go on-site to investigate and analyze all energy-consuming building systems in order to optimize operation and ensure continued performance over time. We streamline the process by using calculator tools for smaller measures and developing custom calculations for larger, more complex measures. Our proven EBCx toolkit ensures consistent technical work and reporting across all projects.
  • Analytics-Enabled EBCx. We employ vetted EIS tools to remotely screen candidate buildings and identify potential measures in advance of the on-site audit. This way, we can approach customers with a clear idea of where opportunities to save energy exist in their specific buildings. This elevates the rate of project commitment and allows the EBCx process to move more quickly and cost-effectively.
  • Monitoring-Based Commissioning. We use remote energy system metering and control system trending to identify inefficiencies and support persistence and continuous improvement after the initial RCx process is complete. This service can stand alone or augment either of the other programs.

We can customize each program for individual markets and serve buildings across the commercial spectrum, from offices to airports, from 30,000 to 4,000,000 square feet. All it takes is integrating the optimal set of people, processes and tools:

  • People. We recruit local engineers and use our extensive library of EBCx best practices, guidelines and templates to prepare them to properly screen and audit target buildings.
  • Process. We tailor the screening and audit processes, measure scope, program steps, budgets and incentives according to targeted market segments, client goals, success metrics, timelines and budgets.
  • Tools. We use the same criteria to select and deploy the right tool or mix of tools, from prescriptive measure checklists to fully-automated software packages, like EIS.


In our experience implementing EBCx pilots and programs, we have:

  • Developed widely-adopted EBCx guides, tools and trainings for the U.S. EPA, Natural Resources Canada, ASHRAE, the California Commissioning Collaborative and the National Conference on Building Commissioning (NCBC)
  • Completed 226 projects between 2004 and 2013 that accumulated more than 73 million kWh and 945,000 therms of first-year savings
  • Tested 13 pilot programs for new methods for EIS integration, including a full-scale Analytics-Enabled EBCx program for 40 buildings
  • Received Awards for EBCx programs and pilots from the American Council for an Energy-Efficient Economy (ACEEE), ASHRAE and the Association of Energy Service Professionals (AESP)

Do You:

See the role of EBCx growing in importance in your portfolio?

Have experience with EBCx programs but are dissatisfied with their scale and/or ability to reach buildings of various types and sizes?

See opportunity for EIS to bring reliability and cost-effectiveness to EBCx programs?

Have commercial customers with interval meters in place?

Have commercial customers that are asking for more energy efficiency offerings?

Need to save energy from a market with immense potential?

If so, we can help. To contact a regional representative near you or submit a more specific request for information, visit our Contact page