Welcome to CalCERTS!


What is a blower door and what does it test?

A blower door is a diagnostic tool used to evaluate the infiltration or air-tightness of a building by artificially inducing a pressure across the building shell. A calibrated fan is used to depressurize the building to a standard test pressure of 50 Pa, the pressure that would be required to pull a column of water up a straw 0.2” (very small). The airflow through the calibrated fan required to maintain a pressure of 50 Pa is recorded in units of CFM_50 and can be related to the building’s ‘natural’ infiltration rate by means of conversion factors related to the buildings dimensions and other site conditions.

What is TDV?

TDV stands for time dependent valuation. TDV is a methodology used in California’s Title 24 Energy Efficiency Standards to account for the total energy used on site as well as the associated cost to the infrastructure for time-of-use patterns and source fuel type. TDV energy accounts for the energy used at the building site and consumed in producing and in delivering energy to a site, including, but not limited to, power generation, transmission and distribution losses.

HERS (Home Energy Rating System)

What is a HERS Rater?

A HERS Rater is a person who has been trained and certified by a HERS Provider to perform Field Verification and Diagnostic Testing as required to demonstrate a buildings compliance with California’s Energy Efficiency Standards (a.k.a. Title 24).

HERS Raters are independent professionals who have been certified by an approved HERS Provider (CalCERTS) to act as third-party special building inspectors on behalf of the local code enforcement agency. By law, Title 20 – HERS Regulations, HERS Raters are required to be independent of the person or company whose work they are inspecting. HERS Raters are expected to act with the professional demeanor and integrity that would be expected of the local Building Official.

The CalCERTS website provides a Rater Directory to help you locate a HERS Rater in your area. Please visit for more information.


What is a HERS Provider?

HERS PROVIDER is an organization that administers a home energy rating system as described in Title 20 – HERS Regulations.

CalCERTS is a private company which has been approved by the CEC (California Energy Commission) to operate as a HERS Provider. HERS Providers are responsible for the training, certification and quality assurance of the HERS Raters they certify. Additionally, Providers must maintain an electronic database, the Registry, to process HERS inspections and issue certificates of compliance associated with those inspections. CalCERTS’ status as a HERS Provider is conditional and requires ongoing CEC approval of all training materials, candidate certifications, Registry operations and quality assurance processes.


How do I become a certified HERS Rater at CalCERTS?

“Compliance Rating” describes a number of field inspections and tests performed by a 3rd party HERS Raters on behalf of the local building department. Also known as FV/DT (field verification and diagnostic testing), HERS verifications are always distinguished by a pass/fail criteria.

CalCERTS maintains three levels of certifications for Compliance Raters based on different sections in the energy codes:

  1. Alterations – Based on the requirements of §150.2 in the 2013 Energy Efficiency Standards. This is the core training that all Raters must successfully complete and is a pre-requisite for subsequent certifications.
  2. New Construction – Based on the requirements of §150.1 in the 2013 Energy Efficiency Standards.
  3. Non-Residential – Based on the requirements of §140.0 in the 2013 Energy Efficiency Standards.

Alterations training requirements:

  • Classroom training (4 days)
    • Class I – HERS Basics
    • Class II – Hands-On Lab
    • Class II – Refrigerant Charge
    • Class III – Residential Alterations
  • Compliance Field House, 2 hour practical exam. Scheduled independently by candidate. (see FAQ entry on Compliance Field House below)
  • EPA-608 Certification
    • Candidates must provide proof of their EPA Type II certification (not included in CalCERTS training). Visit for more information.
    • Not necessary to participate in Class II – Refrigerant Charge, but must be on file with CalCERTS to complete certification.
  • Annual Subscription Fee: $120.00 (subject to change)

New Construction training requirements:

  • Completion of Alterations training requirements (above).
  • Classroom training (2 days)
    • Class IV – Newly Constructed Homes

Non-Residential training requirements:

  • Completion of Alterations training requirements (above).
  • Classroom training (1 day)
    • Class V – Non-Residential Buildings

For more information please visit the training page on CalCERTS’ website or send inquiries to


What are the 2013 Compliance Field House Requirements?

The Compliance Field House is a 2-hour practical exam in which the Candidate must independently demonstrate their ability to perform the tasks associated with HERS ratings. During the exam candidates will be expected to perform 4 basic verifications following test protocol and compliance criteria established by the 2013 Energy Efficiency Standards (Title 24, Part 6):

  1. Total leakage duct test,
  2. Blower door test,
  3. Airflow / Fan-Efficacy, and
  4. Refrigerant Charge.

For each of the four elements, the Candidate must demonstrate to the satisfaction of the Proctor their ability to accurately collect pertinent site information, perform diagnostic tests and evaluate the compliance status (pass/fail) without assistance.

The field house is an open-book exam. Candidates should bring their CalCERTS Training Manuals, pencil or pen, calculator, clipboard, and notepad. The exam Proctor will provide all necessary diagnostic equipment for the exam however, Candidates with their own equipment may bring it if they feel more comfortable using their own equipment.

Before attending a compliance field house, Candidates must successfully complete Alterations classroom training: Classes I, II and III. The Compliance field house is scheduled independently from classroom training and requires an additional proctoring fee. Additional information is available on the training page of the CalCERTS website:

Compliance Field House Exam Policy

  1. Candidates must schedule and pass the Compliance Field House practical exam within six months of completing all course work required for certification as an Alterations rater (Classes I, II & III) . Six months will start with the attendance date of the final class regardless of whether all written exams associated with those courses were passed.
  2. Any written exam re-tests from the associated course work must be completed before attending the field house and within the same six month window. Candidates who fail to pass written exam re-tests shall be required to re-take the associated class at full cost. If during this period the six month window expires for the field house, the candidate will also be required to re-take Class II – Hands-On Lab, at full cost and will then have another 6 month window to pass the Compliance Field House.
  3. If a candidate fails their first attempt at the Compliance Field House, then the one allowed re-test of the field house must be completed within the original six month window. Candidates who fail to pass the Compliance Field House within six months, or who exhaust their re-test eligibility, shall be required to re-take Class II – Hands-On Lab, at full cost and will then have another 6 month window to pass the Compliance Field House.

For additional information about any of our trainings call 916-985-3400 x301 or e-mail


What other work may a HERS Rater perform without violating Title 20?

Title 20, the HERS Regulations, set the rules by which all stakeholders in the HERS process must operate. To avoid the potential for a conflict of interest, Title 20 prohibits HERS Raters from working on any project in which they may have a financial interest (beyond the fee charged for HERS Ratings). The HERS Rater must be independent of the person or company whose work they are inspecting.

However, there are other services that a HERS Rater may offer to the Installer/Contractor, as a consultant, without violating the conflict of interest rules. Additional services typically include working as an Energy Consultant, permitting services and document author support in the Registry.

When there is any uncertainty, HERS Raters are encouraged to contact CalCERTS’ QA supervisor for clarification regarding Title 20 and conflict of interest rules. E-mails should be directed to

Where can I get additional training?

Local utility districts offer training on a wide variety of energy efficiency related topics. Usually free or of nominal cost, utility training is rate payer funded through the CPUC (California Public Utilities Commission).

In addition to being an avenue for continuing education, these classes also offer an excellent opportunity to network with other industry professionals. Bookmark their websites and check their training calendars regularly. The best classes fill up quickly

PGE (Pacific Gas and Electric)

SMUD (Sacramento Municipal Utilities District)

SoCal Gas (Southern California Gas)

 SCE (Southern California Edison)

 SDGE (San Diego Gas and Electric)




CalCERTS Registry

How do I learn to use the CalCERTS Registry?

CalCERTS maintains a library of instructional videos and recorded webinars on its website On the right side of the homepage there is a link for “Instructional Materials.”


How can I create a ‘certificate’ for duct testing when no HERS verifications are otherwise required?

Occasionally there will be circumstances when a consumer, building department or other stakeholder will request a HERS Rater to test a duct system even though there are no Title 24 HERS verification requirements. The CalCERTS Registry supports two certificates for this purpose.

  1. AHV (additional HERS verification) – When there is a building permit for the project but no HERS verifications are triggered by the work-scope of that permit an AHV certificate can be generated.
  2. Consumer Certificate – When there is no building permit associated with the project a Consumer Certificate can be generated.





Test Equipment for HERS Raters

What test equipment do I need as a HERS Rater?

Following are several representative examples of equipment used by CalCERTS’ QA Field Inspectors. These examples should not be considered an explicit recommendation of one brand over another.

Duct Testers, Blower Doors, and Manometers

  • The Energy Conservatory and Retrotec Inc. are the primary manufacturers of these tools.

Visit their respective websites for more information including free PDF downloads of user manuals and other useful technical information.

Smoke Machine

  • Chauvet H1100 fog/smoke with wireless controller

Choose a smoke machine with similar output capacity typically rated in watts. Smoke machines with some type of remote control are strongly recommended.

Flow Capture Hoods

  • TSI Accubalance 8371- 30-2,000 cfm
  • TSI Alnor EBT731- 25-2,500 cfm
  • Kanomax 6710 TABmaster- 25-2,500 cfm

All of the flow capture hoods come with a 2’x2’ hood standard. However, many projects will require a larger capture that can be purchased separately. A 2’x3’ or 3’x3’ hood is also recommended as this fits most returns.

True Flow Grid

  • Energy Conservatory – Trueflow Air Handler Meter

Power (watt) Meter

  • Watts-Up or Kill-a-Watt, Plug-in style
  • Extech 380940, Clamp-on style

Most Raters will want to have both a plug-in style and clamp-on style power meter.

Digital Refrigerant Gauges

  • Testo 550, includes 2 clamp-on thermocouple probes
  • Fieldpiece SMAN-3, includes 2 clamp-on thermocouple probes
  • Fieldpiece SMAN 460, includes 2 clamp-on thermocouple probes

CalCERTS HERS Raters are required to purchase two sets of hoses for their refrigerant gauge with one set dedicated to each type of refrigerant commonly encountered: R410a and R22.

Hose-end fittings with a core-stem depressor are recommended as they simplify connection and removal of gauges to the system without the possibility of accidental refrigerant release. At a minimum, hoses should have a ¼ turn shut-off valve.

Raters will need a ‘key’ for removal of locking caps on the condenser service access valves.

Digital Thermometer

  • Fieldpiece ST4 Dual channel Thermometer
  • K-type thermocouples

Although digital refrigerant gauges have a digital thermometer built in, a separate dual channel digital thermometer will be necessary for simultaneously collecting other required temperatures.

Duct Sealing

  • Vent Caps
  • DucBlocs – Sierra Building Science
  • Grille Mask, masking tape, Press-n-seal

Miscellaneous Equipment:

  • Computer and access to the internet
  • Ladders (4’, 6’, 8’, extension)
  • Safety Equipment (dust mask, safety glasses, gloves, etc.)
  • Digital Camera
  • Flash Lights
  • Hand Tools (screw drivers, nut drivers, cordless drill, step bits, etc.)
  • Booties, Tarps, drop cloth
  • Cordless vacuum cleaner




Work Scope Definitions

In an Alterations project, whether HERS verifications are triggered is primarily determined by two factors; the climate zone in which the project is located and the scope of work that is performed. Following are definitions of work scope from the Efficiency Standards which HERS Raters must know in order to perform their job.

What is an entirely new SC (space conditioning) system?

A system in an existing dwelling unit shall be considered an Entirely New or Replacement Space Conditioning System (SC System) when:

  1. The air handler and all of the system’s heating and cooling equipment (e.g. outdoor condensing unit and indoor cooling or heating coil for split systems; or complete replacement of a package unit) are new, and
  2. The duct system meets the definition of an Entirely New or Replacement Duct System.

See definition of new duct system below.


What is an entirely new (or replacement) duct system?

An altered duct system installed in an existing home shall be considered an Entirely New or Replacement Duct System when:

  1. At least 75 percent of the ducting material is new, and
  2. Any remaining components from the previous duct system are accessible and can be sealed (e.g. register boots, plenums, etc.).

See definition of accessible below.

New Duct System, Only (aka “re-duct”). Special case of a new duct system specifically defined as a new duct system with no alterations performed on any other portion of the system (i.e. new ducts with the original equipment).

Existing Duct System. Altered duct systems that do not meet the definition of Entirely New or Replacement Duct Systems shall be considered an extension of an existing duct system.


What is an altered system/change-out?

Space conditioning systems that do not meet the definition of Entirely New or Replacement Space Conditioning Systems shall be considered Altered Space Conditioning Systems. Change-outs are further classified by whether they involve refrigerant containing components. Examples of change-outs that may trigger HERS verifications include: Installing or replacing a furnace, air-handler, heating or cooling coil, condensing coil or adding/replacing >40’ of ducts in unconditioned space.


What is a refrigerant containing component?

Refrigerant charge verifications may be required when a SC (space conditioning) system is altered by installation or replacement of refrigerant containing system components: condensing coil, compressor, evaporator coil, metering device (TXV, EXV), and/or refrigerant piping (lineset).

Note: Specifically for A/C Condensers and evaporator coils there is overlap between the definitions of work scopes for refrigerant containing component and altered system/change-out. For these components, both work scopes must be considered in determining HERS verification requirements.


Technical Support

Registry Technical Support
Mon-Fri: 7am-4pm
916-985-3400 ext. " * "

Field Tech Support
Mon-Fri: 8am-5pm
916-985-3400 ext. " # "


31 Natoma St Suite 120
Folsom, CA 95630
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Office: 916-985-3400
Toll Free: 877-HERS-R8R (877-437-7787)
Fax: 916-985-3402