Introduction
If you've worked on a California construction project that requires Title 24 compliance, you've likely encountered two documents with similar-sounding names: the CF2R and the CF3R. They're easy to mix up — and mixing them up can cause real problems at inspection or final permit sign-off.
These two certificates serve different purposes, are created by different people, and represent different stages of the compliance process. This post explains exactly what each document is, who is responsible for it, and how they work together to document that a project meets California's Building Energy Efficiency Standards.
What Is a CF2R?
The CF2R is the Certificate of Installation. It is a document completed by the installing contractor — not a HERS Rater or energy consultant — to certify that specific energy-related measures were installed according to the requirements listed on the compliance documentation.
The "2" in CF2R refers to its position in California's compliance documentation sequence: it comes after the CF1R (the compliance report prepared by the energy consultant) and before the CF3R (the field verification).
The CF2R is specific to each trade and measure. Common CF2R forms include certificates for insulation installation (the insulation contractor certifies the type, location, and R-value of insulation installed), HVAC installation (the HVAC contractor certifies equipment model numbers, efficiency ratings, and installation details), duct installation (documenting duct system configuration and materials), fenestration or windows and glazing (the installer certifies that windows and doors match the U-factor and Solar Heat Gain Coefficient values on the CF1R), water heating systems, and lighting systems.
The licensed contractor responsible for installing each measure fills out the relevant CF2R. An insulation subcontractor fills out the insulation CF2R. The HVAC contractor fills out the HVAC CF2R. Each contractor signs and dates their respective certificate, attesting that the installation matches what was required.
The CF2R is submitted to the HERS Registry (the online system maintained by CEC-approved rating organizations such as CHEERS) before or during the HERS Rater's site visit.
What Is a CF3R?
The CF3R is the Certificate of Verification. It is generated after a certified HERS Rater (or in some cases an Acceptance Tester) performs field verification and diagnostic testing to confirm that the installations documented on the CF2R are correct and that the systems perform as intended.
Where the CF2R is a self-reported document completed by the installer, the CF3R is an independently verified document. This distinction is fundamental to how California's compliance system works: installation is self-certified, but verification requires a third party.
The CF3R records the results of field testing and verification performed by the HERS Rater. Depending on the measures on the project, this may include duct leakage test results (actual measured leakage percentage from diagnostic testing), refrigerant charge verification (measured superheat or subcooling values confirming proper charge), airflow measurements, window verification (rater confirms installed product matches CF1R specifications), insulation verification (rater visually confirms insulation quality and coverage), and ventilation system verification.
The CF3R is generated through the HERS Registry system once the rater completes and submits their field verification data. The rater does not manually write the CF3R — the registry produces it based on the data submitted.
CF2R vs CF3R: A Side-by-Side Comparison
The CF2R is the Certificate of Installation, created by the installing contractor, after installation but before HERS inspection. It certifies that the measure was installed correctly and is self-reported.
The CF3R is the Certificate of Verification, created by the HERS Rater via the HERS Registry, after HERS field verification. It certifies that the installation was independently verified and is not self-reported — it requires third-party verification.
Both documents are required for permit final on any project where HERS-verified measures are specified on the CF1R.
Why Both Documents Are Required
The CF2R and CF3R work together as a checks-and-balances system. The CF2R establishes what the contractor claims was installed. The CF3R confirms — through independent testing — that those claims are accurate and that the systems perform as designed.
California's Title 24 compliance system is built on the premise that self-reporting alone is not sufficient for energy compliance. Third-party field verification (the CF3R) closes the gap between what was designed, what was installed, and what actually performs.
Without a completed CF3R for every required HERS measure, a project cannot receive final occupancy approval. Local building departments rely on these documents to confirm that the energy features claimed in the permit were actually delivered.
Common Mistakes to Avoid
Confusing who is responsible for each document is one of the most common errors. Contractors fill out the CF2R. HERS Raters generate the CF3R. These are not interchangeable, and one professional cannot complete both for the same measure.
Waiting until the end of the project to coordinate with a HERS Rater is another frequent mistake. The CF2R should be submitted before the rater's visit, and certain tests (like insulation verification) must happen before drywall is closed up. Scheduling the HERS Rater early avoids costly re-work.
Finally, don't assume the CF2R and CF3R cover the same measures. Each form is measure-specific. A project may have multiple CF2R forms (one per trade) and multiple CF3R certificates (one per verified measure or system). Confirm with your HERS Rater exactly which forms are required for your project.
Conclusion
The CF2R and CF3R are both required parts of California's Title 24 compliance process, but they serve distinct roles. The CF2R is a contractor's self-certification of installation. The CF3R is a HERS Rater's independent verification that the installation was done correctly and performs as required. Together, they document the full compliance trail from design to field.
If you're planning a project that requires Title 24 compliance, make sure your contractor team understands their CF2R responsibilities — and connect with a certified HERS Rater early so the CF3R process goes smoothly.