HERS Testing/Rating

Home Energy Rating System (HERS) In the first few pages of the Title 24 report there will be a “HERS Feature Summary” This is very important to review and understand before even bidding a project. These are all items that are to be third party verified. Some Like QII are at specific stages during construction and it can be very problematic if the elements are not incorporated or are not observed. There are various types of HERS verifications and ratings; These verify that best practices are used in the  installation of new or replacement systems. The 2019 and current 2022 energy code includes some mandatory HERS verifications for all projects as well as additional HERS measures used in Title 24 energy models to gain compliance.

Verification of Title 24 Measures:

  • Maximum Duct Leakage (mandatory max 5% of airflow)
  • Ducts in Conditioned Space
  • Quality Installation of insulation (QII)
  • Blower Door infiltration tests
  • Duct Leakage to Outside
  • Ventilation air flow (mandatory ASHRAE 62.2 levels)
  • Verify existing conditions

All new homes with ducted systems must be verified to have a maximum leakage of 5%. Also it is required that the systems be sized using ACCA manual D, J and S methods. These reports need to be provided to the HERS Rater.

New duct systems in any climate zone must be verified to have a maximum leakage of 5%. Any addition or alteration of air conditioning triggers further testing like for Airflow and Fan Watt Efficacy and possibly Refrigerant Charge. 

Quality Installation of Insulation (QII)
The current code pretty much requires QII for new homes a vary rigorous procedure of air-sealing and insulation Contact HERS rater at the design stage.

Ventilation is now mandatory as per ASHRAE 62.2 and the levels must be verified by measuring air flow to meet or exceed the CFM in the Title 24 report. Applies to all new homes and where the addition is greater than 1000 square feet