Commissioning

What is commissioning?

Understanding the process for realizing efficient buildings that meet the requirements of their owner.

By Jordan & Skala Engineers August 17, 2021
Courtesy: CFE Media & Technology

Just as the term suggests, the duties of Systems Commissioning follow a methodical process by which the design, installation, and operation of building systems are quality-checked and functioning as intended. From pre-design through completion and into initial occupancy phases, Building Commissioning checks each box down the line to meet the Owner’s Project Requirements (OPR). And it’s been found that buildings that have been properly commissioned typically show a higher level of quality and consistency (improved overall quality with fewer change orders during construction, reduced occupant complaints, and fewer warranty issues. A properly commissioned project often benefits from an increase in the building’s overall energy-efficiency and performance as the building’s systems (from Mechanical Electrical, and Plumbing Engineering (MEP)fire and security, to specialty systems) are verified to be installed correctly and operating properly.

What is Commissioning?

Commissioning is a collaborative process designed to document, verify, and optimize building systems to ensure they meet a set of defined requirements and objectives. As it pertains to the built environment, the Commissioning (Cx) process involves detailed planning, documentation, and verification procedure to confirm that any energy-using buildings system (HVAC, Domestic Hot Water Systems, Lighting, Renewable Energy Systems, etc), and its controls are installed correctly and able to operate and be maintained as the design intends.

Beginning with the commercial provisions of 2012 IECC (International Energy Conservation Code), mechanical and lighting systems commissioning became a requirement of the energy code, as well as under ASHRAE 90.1-2010, an alternative compliance pathway for the 2012 IECC.  Likewise, both LEED and ENERGY STAR  incorporate fundamental and enhanced forms of the commissioning process in order to certify a building built to those standards and to receive any necessary credits such as enhanced commissioning.

What are Functional and Acceptance Testing?

Although intertwined and often confused, functional testing, acceptance testing, and building commissioning all apply to different aspects of the design and construction process.  Functional and acceptance testing are checklist-based procedures used to ensure that requirements were met during the closeout process.  Building commissioning, however, is an integral part of the entire construction process that begins in the design phase of a project and continues all the way through until the building is handed over to the owner, or in cases of retrofitting a building, ensuring new systems are placed into working order with any original systems.  ASHRAE defines building commissioning (or Cx) as “a quality-oriented process for achieving, verifying, and documenting that the performance of a building, and its various systems, meets the defined objectives and criteria.”  Finally, the commissioning process ensures the building owner receives a building that operates and functions according to the owner’s project requirements (OPR) and the basis of design (BOD).

Functional testing is a customized test procedure that is performed to ensure the requirements of the specific design are met.  These requirements typically come from the OPR and are performed as a scheduled event.  Acceptance testing is not design-specific but instead ensures that a system meets code and manufacturers recommendations.  The design of a building may often have specifications that are more difficult to achieve than the code requires.  Because an owner’s requirements for the design are typically more stringent, it is not uncommon for a design to pass acceptance testing (the design meets or exceeds the code requirements), but fail functional testing (the installed system is not meeting the requirements of the owner). The commissioning authority’s job (CxA) is to ensure that functional testing is passed and the design is fulfilling the owner’s project requirements and the basis of design (BOD).  After functional testing, if deficiencies are found, the CxA will recommend the specific changes to be made.  If no deficiencies are found, the CxA often recommends that the owner accept the building asset.

Courtesy: Jordan & Skala Engineers

Courtesy: Jordan & Skala Engineers

Benefits of Commissioning

While functional and acceptance testing are both important aspects of the systems installation process, they are applied retroactively to test whether installed systems meet the manufacturer requirements during installation (acceptance testing) and once operational (functional testing). The commissioning process is a guiding hand along the way, helping to produce a superior asset that outperforms its non-commissioned counterpart by getting involved early in the pre-design phase and staying involved all the way through closeout and acceptance of the building asset by the owner.

Commissioning provides a variety of different benefits especially when deployed early in the design phase; a commissioning agent (CxA) should be involved to help develop the intent of the design, the Owner’s Project Requirements (OPR), and the Basis of Design (BOD).  By getting involved in these initial stages, the CxA can help carry that message through every phase of the process, whether it be new construction or a retrofit situation, and ensure the entire process follows the contract requirements. The commissioning agent (CxA) is responsible for carrying out the detailed planning and implementation of the commissioning process.

In addition to enhanced energy efficiency, utilizing commissioning can benefit building owners through improved workplace performance thanks to the verified indoor environmental air quality and the prevention of business and energy losses. Plus, reducing any future downtime means the building can stay operational longer with higher owner/occupant satisfaction.

What’s involved in Commissioning?

Commissioning ensures that the building’s systems are all installed and operating as designed.  A skilled commissioning agent will have experience with all the systems listed in the commissioning plan.  He or she should know what systems are required either for code compliance or for a particular green building program.  Some of the main systems that are involved in commissioning are:

  • Mechanical Systems (HVAC/heating and cooling systems, ventilation and outdoor air delivery, ductwork and system controls)
  • Electrical (Power Distribution, Lighting, Lighting Controls)
  • Plumbing (Hot Water, Process Water, Water Distribution, Sanitary, Storm Runoff)
  • Protective Systems (Fire Suppression or Lightning Protection)
  • Building Envelope (the building’s roof, foundation, walls; any physical separation between conditioned and unconditioned elements)
  • Communication Systems (Telecom, Sound, Video)
  • Alarm Systems

The four main types of Commissioning

Throughout the lifecycle of a building, commissioning has a role to play.  Assurance that a building is functioning as the design intended is needed for new construction and during renovations, as well as periodically while the building is in service.  In order to address these different needs, there are four main types of commissioning:

NEW CONSTRUCTION COMMISSIONING

The most common type of commissioning is for new construction and is often also the most impactful because it allows the commissioning process to start in the pre-design phase and help inform design decisions before they are made. A commissioning plan is created during the design phase to ensure that the building’s planned systems perform according to the design intent and the owner’s operational requirements.  The basis of design, the owner’s operational requirements, and the commissioning plan can then all be used as a roadmap throughout the design and construction process to ensure that the finished product will fulfill the original intent of the design.   Functional testing is used throughout the construction of the building to check that the requirements of the OPR and BOD are being met and to identify potential building system issues. At the end of construction, a commissioning report is issued and includes a narrative of how each system is intended to operate, including suggested setpoints which helps prepare the operations personnel to maintain the facility once the building is occupied.

RE-COMMISSIONING

The second type of commissioning is re-commissioning.  Although a building may have passed its new construction commissioning, building systems age and preventative maintenance schedules are not always followed as intended.  Much of the process is the same as for new construction.  The building’s operations and maintenance (O&M) personnel work alongside the CxA to verify equipment and systems are operating as designed. By repeating this commissioning process periodically throughout a building’s usable lifetime, this re-commissioning can verify specific system efficiencies or identify potential catastrophic failures before they occur. Though not a substitution for regular preventative maintenance, re-commissioning is an additional process to make sure that all systems continue in good working order.

RETRO-COMMISSIONING

Further along the timeline of a building’s lifetime is retro-commissioning. This form of commissioning often focuses on energy-using equipment and systems such as HVAC, lighting, and related controls.  The goal of retro-commissioning is often to reduce energy waste, obtaining energy cost savings for the owner, and to identify and fix existing problems in a building that has not previously been through the commissioning process, or one that has fallen out of regular maintenance and re-commissioning.  Through diagnostic testing and data gathering, the commissioning agent will test the building systems and tune their performance or recommend system upgrades or replacements and restore the systems to the original design intent.

MONITOR-BASED COMMISSIONING

The fourth and final type of commissioning is Monitoring-Based Commissioning or MBCX, a newcomer to the building commissioning scene.  MBCX leverages technology and innovative commissioning techniques to integrate energy management in a continuous fashion. Think of it as an ongoing process, wherein Monitor-Based Commissioning allows the commissioning agent to take a real-time look into building systems and operations, to fine-tune the system operations and identify areas that need improvement.

What is enhanced Commissioning?

While fundamental commissioning plays an integral role in designing and building energy-efficient buildings, enhanced commissioning is a term originating from the LEED Rating System, and is a voluntary process that a building owner can choose to pursue in order to receive additional credits in green building programs.  Enhanced commissioning builds upon fundamental commissioning and provides a few different pathways in order to verify that a building is exceptionally energy-efficient.  Many of the requirements of enhanced commissioning require more extensive post-build documentation or more extensive commissioning practices.  Some of the most common requirements are listed below:

  • Drawing design review
  • Reviewing contractor submittals
  • Verifying the inclusion of systems manuals in construction documents
  • Developing monitoring-based procedures and identifying points to be measured
  • Conducting envelope commissioning
  • Ensure building operators are trained on the installed systems

How to Select a Commissioning Agent (CxA)

As important as the commissioning process is, the selection of a reputable and qualified commissioning agent is arguably the most important part. The commissioning agent (CxA) helps ensure the project avoids unnecessary time-consuming design and performance issues.  One of the first qualifications to look for in a commissioning agent is any previous experience on similar projects.  If the agent has worked on a similar project or is familiar with the building systems, he or she can more readily identify problems and potential pitfalls before they occur.

The next most important requirement is that the agent does not have any conflicts of interest.  He or she must be able to make decisions independently of the design and construction teams. Ideally, the CxA will be a third-party to the general contractor as well. The CxA must be able to highlight concerns during the design and build process that are in the best interest of the owner and follow the intent of the design.  Because of this, many programs recommend that the CxA be contracted for the project directly by the owner, removing any middleman.

Once these requirements are satisfied, the next attributes that a CxA should have are strong communication and interpersonal skills as they will be communicating with many different parties during the commissioning process including the owner, engineers, and architects on the design team, and many different trades and disciplines on the construction team. After the build is complete, the CxA will also work with the building’s O&M staff. Effective communication helps the process move along smoothly which results in a finished building that matches the intent of the design and a more satisfied owner or operator.

One last thing you will want to have in a CxA is field-experience in the construction industry and testing/troubleshooting experience.  An individual with hands-on experiences along with design experience will often be an irreplaceable member of the team. Seek out a CxA who has one of the following commissioning certifications or awards to be sure their experience and training are sufficient to head up your project:

As a recipient of the NGBS Green Partner of Excellence Award, and recognized MEP Giants for over 15 years, the sustainability team at Jordan & Skala Engineers are trusted partners in the built environment. From new construction to retrofitting, commissioning by Jordan & Skala will guide your project and system requirements through each phase to ensure proper integration and functionality.

Courtesy: Jordan & Skala Engineers

Courtesy: Jordan & Skala Engineers

What is the Commissioning Process?

Overall, the commissioning process consists of four phases: the design review phase, the construction phase, the acceptance phase, and the operations phase. In the design phase, most of the commissioning process involves reviewing the architects’ and engineers’ early designs to verify that they satisfy the owner’s project requirements. During the construction phase, the role of building commissioning is more focused on performing site observations and verifying that pre-function checklists are completed and functional tests are performed.  In the acceptance phase, the commissioning agent will complete the functional performance system testing and coordinate the owner’s personal training.  Moving into the operations phase, the commissioning efforts are focused on completing the commissioning report, generating operations and maintenance plans, compiling final system manuals, and developing an ongoing commissioning plan.

At the completion of the fourth phase, the new building owner should be in full acceptance of a building that meets the original requirements laid out during the pre-design phase. Building commissioning is more than just a functional checklist, but a process for realizing efficient buildings that meet the requirements of their owner.

This article originially appeared on Jordan & Skala’s website. Jordan & Skala Engineers is a content partner of CFE Media.


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