HERS testing, ECC verification, and who does it

Testing what actually got built

HERS field verification is third-party testing of specific energy measures in the building as it actually gets built — duct leakage, refrigerant charge, insulation quality, ventilation airflow and similar — carried out by an independent rater who had no hand in the construction. Under the 2025 Energy Code the same function is called ECC verification, short for Energy Code Compliance, and the person doing it is an ECC-Rater rather than a HERS Rater.

It exists because an energy model is a set of promises. The CF1R says the ducts will leak no more than a set amount, and the insulation will go in without gaps or compression. Nobody can tell that from a drawing, so the code puts a second party on site with instruments. The CEC states the purpose plainly: the program verifies that new residential buildings, additions and alterations comply with the standards, in order to protect consumers from poor construction and installations. Everything below is single-family work; three-plus-unit low-rise buildings run on the LMCC certificate instead.

HERS or ECC — which word applies to your permit

Both, depending on the code cycle. As of January 1, 2026 all HERS Providers are recognized as ECC-Providers and all HERS Raters as ECC-Raters, and field verification moved from the Title 20 HERS regulations into the Energy Code — Title 24, Part 1, Section 10-103.3. It is not retroactive: the version of the code that was in effect when the project was permitted stays the applicable version, so a 2022-cycle project is still rated to 2022 standards.

Compliance documents from earlier cycles keep saying HERS; only 2025-cycle documents say ECC. The HERS name survives with a narrower scope — whole-house ratings and home energy audits, which do not support Title 24 compliance — and rater companies may keep HERS in their business names. If you are looking for a rater, HERS is still the word most of the industry uses. The glossary has both terms in short form.

Which measures trigger it

The measures do, not the project type, and only what actually gets installed counts: a house with no ducts needs no duct leakage test. Some triggers are mandatory. Duct sealing and leakage testing is mandatory whenever a space-conditioning system uses forced-air ducts to supply conditioned air to an occupiable space, confirmed by field verification under Residential Appendix RA3.1, so a detached ADU with ducts is in the same boat as a new house. On an alteration that installs or replaces refrigerant-containing parts — compressor, condensing or evaporator coil, metering device, refrigerant piping — refrigerant charge and airflow verification applies to air-cooled air conditioners in Climate Zones 2 and 8 through 15, and to air-source heat pumps in every climate zone; on new construction, Table 150.1-A decides. Duct sealing on an alteration carries three exceptions: ducts already documented as sealed and verified, duct systems under 40 linear feet, and existing ducts constructed, insulated or sealed with asbestos. Most of that lands on change-outs.

The rest come from the performance path. When the model leans on performance better than the prescriptive minimum to pass, that has to be proven in the field. Section 150.1(b)2B lists what qualifies: SEER2, EER2 and HSPF2 ratings above the minimum, the variable-capacity heat pump option, low-leakage air handlers, heat-pump rated heating capacity at 47 and 17 degrees, whole-house fans, central fan ventilation cooling, building enclosure air leakage, and quality insulation installation. That is the part designers do not see coming: a model that squeaks by on a high-SEER2 condenser has bought a field test. The full list lives in Reference Residential Appendix RA2.2, in Tables RA2-1 through RA2-7; no fixed checklist fits every job.

How it shows up on the CF1R

The CF1R is where the list lives. It identifies the features and diagnostic results requiring verification, and the rater’s Certificate of Verification has to match it. On a 2025-cycle report the block is titled ECC FEATURE SUMMARY; on 2019 and 2022-cycle reports the same block reads HERS FEATURE SUMMARY. Blank block, nothing to test. Lines in it, somebody has to go test them.

One consequence at permit time: where compliance requires field verification, the CF1R handed to the building department has to be a registered document from an approved ECC registry, not a form filled in and printed on your own. That is in the flat fee here — I register through CHEERS, approved by the CEC as an ECC-Provider for the 2025 code on November 12, 2025. Not every permit needs a registered CF1R — the CEC still publishes non-registered fillable forms for projects that require no field verification at all.

Who performs it, and who arranges it

An independent third-party rater, and not this service. ECC-Raters are trained, tested and certified by an ECC-Provider, must operate independently, and may not hold a financial interest in the builder, designer or subcontractor signing as the Responsible Person. Nor may they do construction work on a site where they will perform the verification. The CEC calls them special inspectors for the project proponents, installing contractor included — not for the building department, which does not supply the rater.

Arranging one is the builder’s job: if the CF1R indicates ECC verification is required, the builder arranges for a certified ECC-Rater. A homeowner may hire their own rater instead, though contractors commonly offer to take that on. My end does not change either way — I am the documentation author on the CF1R and you stay the responsible designer. I do not do field verification and I do not sell it.

Where it lands in the build sequence

Three certificates, in a fixed order. The CF1R goes in at plan check, before the permit is issued. The installing contractor tests and reports on the CF2R during construction. The ECC-Rater independently verifies and submits the CF3R during the final inspection phase, before the certificate of occupancy — which the building department cannot issue until it has every required compliance document, CF3Rs included.

Some measures pull the rater out earlier. Quality insulation installation has its own framing-stage form, CF3R-ENV-21-H, so QII means a visit before drywall as well as after. Duct leakage can be tested at the rough-in stage too, before the interior finishes go on, and lands on CF3R-MCH-20-H either way. Refrigerant charge waits until the system is installed and running, on CF3R-MCH-25-H. On an HVAC change-out the front of the sequence relaxes: the registered CF1R-ALT-02 may be submitted at final inspection rather than before the permit is pulled.

Prices

Flat fees, in writing before I start. No hourly, no bid package, no change-order games — the number on the quote is the number on the invoice.

One honest note

Field verification questions

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