• Ben Gilbert

Commissioning in California – Whose idea was this anyway?


I have been asked this frustrated or panicked question many times by Engineers, Architects, Contractors, and Owners. And with good reason – Title-24 has made commissioning mandatory for many types of projects over the past few years. Add in the fact that commissioning requirements show up in (2) distinct parts of the code, some projects pursue LEED certification, the San Diego Climate Action Plan includes requirements related to commissioning, and different AHJs tweak the requirements and have varying levels of enforcement, and your head can start spinning.

The short answer to this question is yes, if your project is over 10,000 sq. ft. This applies to new construction and TI’s.

The longer answer is maybe not, for some OSHPD-1 and DSA projects. However, the owners of these projects often have their own project-specific commissioning requirements, typically captured in an RFP.

For now, let’s focus on the first case. Title-24, Part 6 (the California Energy Code), section 120.8 states that “Nonresidential buildings with conditioned space of 10,000 square feet or more shall comply with the applicable requirements of Sections 120.8(a) through 120.8(i) in the building design and construction processes. All building systems and components covered by Sections 110.0, 120.0, 130.0, and 140.0 shall be included in the scope of the commissioning requirements in this Section, excluding those related solely to covered processes.” Clear as mud, right? To summarize, the Energy Code is saying that the following tasks or documentation is required as part of the commissioning process if your project is 10,000 sq ft or more:

1. Owner’s or owner representative’s project requirements (OPR)

2. Basis of design (BOD)

3. Design phase design review (CXR forms)

4. Commissioning measures shown in the construction documents (specs, notes on dwgs)

5. Commissioning plan

6. Functional performance testing (FPTs, ISTs)

7. Documentation and training

8. Commissioning report (includes Systems Manual)

Items 1 through 5 are required to occur during the design phase (starting in early SD!) and may be required for plan check by the AHJ. Items 6 through 8 occur during construction and are required for Certificate of Occupancy. Yes, commissioning is a code requirement for both plan check and C of O.

Title 24, Part 11 (CALGreen), section 5.410.2 is very similar to Part 6 with respect to commissioning. It has the same 8 requirements listed above, but includes the following verbiage: “All occupancies other than I-occupancies and L-occupancies shall comply with the California Energy Code as prescribed in California Energy Code Section 120.8. For I-occupancies that are not regulated by OSHPD or for I-occupancies and L-occupancies that are not regulated by the California Energy Code Section 100.0 Scope, all requirements in Sections 5.410.2 through 5.410.2.6 shall apply.” This is basically saying that your OSHPD project that is going through the city (for example, some OSHPD-3 projects), and your lab projects still require commissioning.

The San Diego Climate Action Plan, commonly referred to as San Diego CAP, went into effect last year. This mandatory initiative came from the mayor’s office, so it’s not on everyone’s radar. This initiative has goals of increasing water and energy efficiency reducing CO2 emissions, among many other things. There are also Monitoring & Reporting requirements which may include some commissioning scope.


This part is simpler. For Title-24, the answer is:

1. HVAC systems and controls. (includes Measurement and Verification devices/systems, when applicable)

2. Indoor and outdoor lighting and controls.

3. Water heating systems.

4. Renewable energy systems.

5. Landscape irrigation systems.

6. Water reuse systems.

For LEED v4, building envelope commissioning is added to the above list as an optional credit.


For projects between 10,000 and 50,000 sq ft, AND have only “simple” HVAC, which is basically rooftop package units or DX split systems (not VRF), the design phase review must be by a true 3rd party company, but the rules are more relaxed for who can do the rest of the tasks. If the project is over 10,000 sq ft and has complex HVAC systems, or, any project over 50,000 sq ft, the commissioning provider must be a true 3rd party (i.e., GMC Commissioning). For a free, helpful ‘cheatsheet’ that includes this information and more helpful tips, contact me at, or check out "Downloads" in the members section of this website.

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