Commissioning insights

• Building commissioning ensures that a building’s systems operate as intended by verifying their design, installation and functionality align with project requirements and energy efficiency goals.
• Codes and standards, such as ASHRAE 90.1, influence the design by mandating efficiency benchmarks and integration of systems like building automation, which commissioning verifies to meet performance criteria and compliance.

The commissioning process in recent years has evolved into a comprehensive quality assurance process that plays a critical role throughout commercial building design, construction and post-occupancy phases, especially as new ASHRAE Standard 90.1: Energy Standard for Buildings Except Low-Rise Residential Buildings (2019 and 2022 editions) requirements set higher energy efficiency standards.

Think of it as test-driving a car — not just to ensure it runs, but to verify it delivers on its promised performance, comfort and safety. Commissioning can no longer just be about functional testing at the end of the construction phase. It now involves collaborating with the owner and design team early and often aligning the building systems with energy goals, identifying potential inefficiencies and ensuring compliance with the new energy code requirements. This proactive approach ensures the building operates as intended from the start, offering long-term benefits to owners and occupants alike.

ASHRAE 90.1 commissioning requirements

ASHRAE 90.1-2019 introduced expanded commissioning requirements to ensure compliance with the increase in energy-efficiency standards. The typical systems to be commissioned are still there: heating, ventilation and air conditioning (HVAC) systems; service water heating systems; and lighting controls.

Figure 1: ASHRAE 90.1-2019 commissioning requirements now include deliverables during the design phase. Courtesy: DLR Group

However, starting with the 2019 edition of ASHRAE 90.1, new systems were introduced that have not been required before. These systems include electrical energy monitoring, whole-building energy monitoring and building envelope testing and verification.

When it comes to ASHRAE 90.1-2022, there are no new commissioning requirements compared with the 2019 edition. The 2022 edition reorganizes the content and refines the commissioning requirements to allow more clarity. For the sake of this article, the topic of discussion focuses on 2019 edition of ASHRAE 90.1, as it is starting to become the standard energy code adopted by many jurisdictions.

ASHRAE 90.1-2019 expands on the commissioning scope from previous editions by detailing specific requirements starting at the design phase through the post-occupancy phase. The purpose of the commissioning process is to provide a systematic approach to identify and correct deficiencies before the building is fully operational, helping owners achieve their energy performance goals.

That cannot be completed effectively unless there is early integration. A terminology misnomer is that “commissioning” is functional testing. Those involved in the industry must understand there is more to commissioning than just functional testing to help move the needle as it relates to energy efficiency. These new commissioning requirements help speak to that commitment.

The commissioning provider’s role

These new requirements result in additional scope and cost that building owners, designers and contractors may not have previously accounted for. Given the relative novelty of these updates, stakeholders face a learning curve in adapting to the standard’s new demands. It is important for the commissioning provider (CxP) to walk through their process early and often on a given project to understand the benefits of implementing these changes effectively as it will result in cost savings and fewer headaches in the long run if commissioning is engaged and performed properly.

Two of the additional commissioning requirements that need to be included are electrical energy monitoring (metering of electrical consumption within the building such as HVAC and lighting systems) and whole-building energy monitoring (metering of utilities to the building produced by a central plant or utility provider such as chilled water and natural gas).

It is important for designers and owners to understand what metering equipment needs to be provided and where. Some common issues with metering equipment are:

• It is unclear who is to provide and install the meter.
• They are not shown in the right location.
• The meter polling frequency does not align with the building automation system (BAS) needs, resulting in incomplete data.

Scheduling a temperature controls meeting with the design team and contractor during the pre-construction phase can help flesh out these controls details along with other controls utility and energy monitoring related questions before procurement and submittal review.

Who performs the testing?

Building envelope is probably the most significant requirement introduced in ASHRAE 90.1-2019 that all parties must be cognizant of as it can result in higher costs if looped in later in the project. There are two paths to satisfy the building envelope verification requirements:

• Building pressurization testing per Section 5.4.3.1.1.
• Continuous air barrier design and verification per Section 5.9.1.2.

Figure 2: Active involvement from the owner and facility operators in the commissioning process leads to improved long-term maintenance. Courtesy: DLR Group

Building pressurization testing has gained traction since the early 2000s with the introduction of U.S. Green Building Council LEED and the option for additional credits. However, testing and verification has only recently become a requirement for projects greater than 10,000 square feet with the introduction of ASHRAE 90.1-2019. It is straightforward to understand the less leakage a building has, the more energy efficient the building will be. In addition, codes are now requiring testing with growing emphasis on verifying building performance versus prescriptive only requirements. Understanding how this affects a given project should be a topic of discussion early in the design process.

As it relates to the option of pressurization testing, ASHRAE 90.1 lists multiple ASTM standards for testing providers to follow. This is key when it comes to the building enclosure specification development because this will allow the contractor to provide better bids for this test. If there is a construction manager on board, then they should also be looped into these conversations early so that no one is caught off guard later in the project.

It is also important to understand who can perform this testing. ASHRAE 90.1 states:

“Verification and testing providers shall be owner’s qualified employees, CxPs, design professionals, qualified designers or qualified technicians experienced with verification or functional performance testing of the designated systems.”

It is not entirely specific because the goal here is to allow for flexibility as it is up to the design team and CxP to discuss what is best for their given project. Again, it is key for the specification to clearly state that the testing agency has the necessary certifications along with documented experience with the listed ASTM standards and projects of similar scope and complexity.

The second option to satisfy the building envelope verification requirements is exception three to Section 5.4.3.1.1 that allows the project to bypass the building pressurization testing through verification of the design and installation of the continuous air barrier. To satisfy this requirement, a design review must be performed, followed by periodic field inspections of the air barrier and the reporting of any deficiencies. An advantage to the exception option is that experience with air leakage testing is not required by the testing provider, which can open the field of qualified providers to perform this service to many — even the CxP.

The goals and requirements for every project are different and conversations should be had to determine the best path forward. Exception three seems to be the more straightforward option and advantageous if schedule and construction costs are a top concern.

To perform the pressurization testing, construction will likely have to be shut down for an extended period to allow for proper measurement to take place. This leads to additional coordination and effort with all the trades on the job. And if the test measurements fail to meet the given leakage requirements, then the pressurization testing will have to be performed all over again. That is not a concern with the exception three option.

However, one might not necessarily have the peace of mind that their building is below the leakage requirements. These are just a few of the conversations that the CxP should be leading to understand what the available options are and who can perform these tasks to provide the best solution for the owner.

Commissioning and testing

As ASHRAE 90.1 is now requiring commissioning activities and deliverables during the design phase, early integration of the CxP is needed to satisfy the activities and certain deliverables during the design phase, which warrants early integration of the CxP these requirements. The documentation to expect from the CxP includes:

• Commissioning plan
• Commissioning design review comments
• Construction commissioning requirements (detailed in the specifications).

Figure 3: Commissioning costs vary based on project size and complexity, but they tend to plateau due to economies of scale. Courtesy: DLR Group

ASHRAE 90.1 Section 4.2.5.2.1 states that the above-mentioned information is to be included in the building permit application. The local authority having jurisdiction (AHJ) has final say what is necessary for a building permit, and it is important to understand that early integration of the CxP is critical for the project and to have the CxP identified early in the design phase.

The functional performance testing (FPT) period is the process that most built environment professionals probably associate with the commissioning process, where the CxP verifies equipment, assemblies and systems meet the defined performance criteria. Unfortunately on many projects, FPT doesn’t begin until the end of the construction phase and sometimes FPT takes place during the occupancy period, specifically for fast-track projects with short construction schedules such as educational buildings that tend to have “summer slam” construction projects.

ASHRAE 90.1 is now requiring an initial round of FPT along with a preliminary commissioning report to be completed before building occupancy. Again, this is up to the AHJ to enforce, but the push here is for testing during occupancy should be the exception. This aims to streamline the building handover process to the owner because it becomes much more difficult to functionally test equipment when there are manual overrides to allow facilities personnel to maintain a comfortable building while construction work is wrapping up.

A good amount of this information may be new to many. The key takeaway is to involve the CxP early in the design phase. This allows the CxP to lead and assist with these discussions by identifying potential issues or hurdles as they relate to new testing requirements and recommending adjustments to meet performance and efficiency goals from the start.

Early engagement enables the CxP to work with the design team to establish clear, achievable criteria for system performance, preventing costly design changes or delays during construction. By setting a foundation for collaboration early, the CxP can help guide the project toward a more streamlined efficient design-build process.

Why commissioning matters

There are some common pain points experienced during the commissioning process for a given project. With the introduction of performance-based standards, it is becoming important to recognize these hurdles and understand how the commissioning process can help deliver a better project. Some of these roadblocks include:

Lack of awareness or buy-in: Project stakeholders, including owners, architects and engineers, may not fully understand the benefits of commissioning or may see it as an added cost rather than an investment. This can lead to pushbacks against incorporating commissioning early.

Budget constraints: Commissioning can be perceived as an unnecessary expense at the design phase, especially if the project’s budget is tight. As a result, commissioning services are sometimes cut or deferred to later stages, where it becomes more challenging to address design issues.

Role clarity and responsibility: When CxP roles aren’t well defined, confusion arises around who is responsible for implementing commissioning recommendations. The design team might also be uncertain about how to collaborate effectively with the commissioning team.

Resistance to change in workflow: Design teams may be accustomed to a certain workflow and may resist adapting to one that includes commissioning input from the beginning. Adding additional steps or checkpoints may be seen as disrupting established processes.

Players in commissioning

Figure 4: Periodic field inspections of the building envelope are becoming more prevalent per ASHRAE 90.1-2019 commissioning requirements. Courtesy: DLR Group

The sentiment about the commissioning process is, at times, it is treated more as a box-checking exercise rather than a quality assurance tool that delivers important value to the entire team. It largely falls on the CxP to take the lead and facilitate team participation. A key to achieving this is ensuring that every team member understands how the commissioning process benefits them.

Designer: A designer would benefit as it allows them to verify that their designs function as intended and meet performance requirements in real-world conditions. Additionally, commissioning offers valuable insights into potential design improvements and fosters collaboration with contractors and facility operators, leading to more efficient and reliable building systems.

Building owner: A building owner’s participation ensures the facility will operate as intended, aligning with their performance and energy goals. Active engagement in commissioning helps owners gain a deeper understanding of their building systems, allowing them to improve long-term maintenance, enhance occupant satisfaction and reduce unexpected operational costs.

Facility operators: Facility operators benefit by gaining firsthand knowledge of the building’s systems, controls and performance requirements, which equips them to operate and maintain systems effectively from Day One. Their involvement allows them to address any operational concerns early on, fostering a smoother handover once the building is fully operational.

Contractors: Contractors can ensure that their installations are correctly implemented and meet the project’s performance specifications, reducing the risk of rework and costly delays. This involvement fosters better communication with the design team and owners, enabling them to clarify expectations and resolve issues proactively, leading to a smoother project closeout and improved client satisfaction.

Active participation by all parties in the commissioning process creates a collaborative environment where design, construction and operational needs are aligned, ensuring the building performs as expected. This teamwork reduces misunderstandings, minimizes costly corrections and leads to a smoother project handover, ultimately delivering an efficient building that meets the owner’s goals and enhances occupant satisfaction — a win-win for everyone involved.

Once the value of commissioning is understood and there is active participation from the team, then additional benefits can be realized. A study conducted by members of Lawrence Berkeley National Laboratory and Building Commissioning Association that reports the commissioning costs and savings across representing 373 million square feet spanning three decades. Per that study, existing building commissioning projects resulted in 6.4% energy savings, a median payback of 1.7 years and a median project cost of $0.26 per square foot.

New construction commissioning projects resulted in 13% energy savings, a median payback of 4.2 years and a median project cost of $1.03 per square foot. Although the savings and value are evident, the value can be sometimes hard to grasp as these savings and efficiencies are somewhat overlooked as design-build professionals tend to focus on construction issues to ensure the project keeps moving forward. Whereas if a CxP was involved early in the design, then ideally that given project would have fewer requests for information, fewer change orders and less finger-pointing.

Creating the commissioning plan

In summary, ASHRAE 90.1-2019 is being adopted as the standard energy code in many jurisdictions. Designers, owners and contractors must understand how its updated commissioning requirements impact their work. Key changes include:

• Early commissioning integration: Commissioning activities and documentation are now required during the design phase.
• Preliminary commissioning report before occupancy: A first round of FPT and a preliminary commissioning report must be completed before the building is occupied.
• Expanded scope: Commissioning requirements beyond HVAC include building enclosure and utility and energy monitoring.
• Increasing AHJ oversight: While enforcement is still up to the AHJ, the new standard encourages stricter adherence to the commissioning process.

Figure 5: Commissioning is starting to integrate systems beyond mechanical, electrical and plumbing engineering, and taking a wholistic approach on total building performance. Courtesy: DLR Group

Ideally, the CxP should serve as a bridge between the owner and the design team by translating technical topics, design strategies and operational needs across all project stakeholders. With a background in engineering, construction or facility operations, a CxP should possess the technical expertise to understand design complexities and the practical experience to anticipate operational challenges. This unique skill set allows for effective communication with both the design team — speaking their technical language — and the owner, who may focus on long-term performance, cost-efficiency and usability.

Active participation and early integration from all stakeholders are critical to commissioning’s success. When stakeholders embrace their roles in the commissioning process and define goals early, they contribute to a building that is not only high-performing but also adaptable to future needs, ensuring long-term sustainability and operational excellence.

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