California is divided into 16 separate climate zones each with their own set of requirements for Title 24 part 6. In order for the home owner or builder to comply with Title 24 they would first start by looking up what climate zone corresponds to the city or county where the building permit is being sought. The next step would be to decide which type of compliance is right for them. Currently there are two ways to comply with Title 24 part 6, the prescriptive method or the performance method. The prescriptive method would be looking up your climate zones requirements and filling out the corresponding hand forms to meet compliance. The performance method would be modeling the building with computer software and the forms would be generated by the software. Typically owners and builders use the performance method for trade offs, for instance if a home owner wanted more windows in their new home the energy that would be lost for adding those windows would have to be made up in another area of the building, like a higher efficiency HVAC unit or water heater.
Third party verification by a certified HERS rater is required for certain energy efficiency features. These include duct testing, refrigerant charge/ air flow measurement and TXV (thermal expansion valve) verification. HERS rater verification is a prescriptive requirement for new construction and some alterations in certain climate zones. There are alternatives and exemptions to the HERS requirements listed in the 2005 Energy Efficiency Standards. The HERS verification can be avoided if is not called for in the performance approach.