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The California Building Standards Code defines the building codes for the state of California. Title 24 of that code defines the energy efficiency standards of the building codes. Since enacted in 1977, the energy commission has reduced electric bills by more than $74 Billion dollars. The standards change over time - and vary by climate location in the state. The standards also differ for commercial and residential applications. 



A written construction permit shall be obtained from the enforcement agency prior to the erection, construction, reconstruction, installation, relocation, or alteration of any mechanical system, except as permitted in Appendix Chapter 1, Section 112.2 of the 2007 California Mechanical Code. Projects requiring permits include, but are not limited to: 

  • New HVAC installation

  • HVAC Changeout

  • Replacement of furnace, coil, FAU, or condenser 

  • Relocation of an existing HVAC unit

  • Adding or replacing more than 40ft ducting in unconditioned space 

HERS verification is required for all HVAC alterations in Climate Zone 10-15. A HERS rater is a special inspector for the building department. The building inspector may also request to be on site to witness testing by the contractor and/or HERS rater. The installer picks one of the four options on the CF-1R-ALT-HVAC Form that describe the work being conducted. Each option lists the forms required to be at the job site for final inspection.

  • CF-2R Forms shall be completed and submitted by the installing contractor for final inspection.*

  • CF-3R Forms shall be completed, registered with an approved HERS Provider.

DESCRIPTION OF HERS TESTS BELOW (Full descriptions found in Residential Appendix RA3 and Residential Manual)

  • Duct sealing – The installer is to insure leakage of the HVAC system is less than 5% for new air conditioning system (new equipment and all new ducts) or 15%, 60% reduction, seal all accessible leaks, etc. for alterations to existing HVAC systems. When the contractor uses the option to seal all accessible leaks, all easily movable objects must be moved to seal existing ducting. New ducting installed by the contractor is not allowed to have any leaks even if it is no longer accessible. In example 3 of the CF-1R “all new ducts” means that all the ducting was changed. The original boots, plenums, etc. do not need to be changed.

  • Cooling Coil Airflow (CCA) – There are two different minimum air flow requirements that must be met. These are 300 CFM and 350 CFM. The minimum 300 CFM per ton of cooling is required in order to conduct a refrigerant charge test. For new HVAC systems (new equipment and new ducts) the HVAC system must move a minimum 350 CFM of air for each ton of cooling.

  • Refrigerant Charge (RC) – The installer is required to verify the charge is correct. If the outside temperature is below 55 degrees then the weigh in method must be used by the installer. When the weigh in method is used the HERS rater must retest when the temperature is 55 and above. A charge indicator display (CID) can be used in place of conducting an RC, manufacturers are currently developing this device.

  • Temperature Measurement Access Holes (TMAH) – Installer must drill and mark holes to measure temperature split.

  • Hole for the placement of a Static Pressure Probe (HSPP) or Permanently installed Static Pressure Probe (PSPP) – Either the installer must drill and mark holes to measure static pressure or a permanently installed pressure probe must be installed and marked. 

  • Saturation Temperature Measurement Sensors (STMS) – Permanently installed type K thermocouple are installed on the indoor and outdoor coil so that the HERS rater can verify charge without attaching gauges. Instructions are found in Ch 4 of the Res. Manual.

  • Fan Watt Draw (FWD) – Installer verifies that the furnace fan watt draw is less than 0.45 Watts/CFM.


We have many of the form you'll need on our site here:


The main resource is the California Energy Commission. Here is their site on Title 24:


Specifically, here is the Residential Compliance Manual:


PG&E also has a good reference site with lots of information for Home Owners:

California’s Energy Efficiency Standards and Title 24
ENERGY STAR Qualified New Homes
Wikipedia on Duct Testing

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