The 2019 residential energy code (2019-Code) will use a new energy efficiency metric to gauge code compliance: the Energy Design Rating (EDR) will replace compliance percent. Each metric accomplishes a similar task – determining if a proposed-home uses less energy than a prescriptive-home of the same size and in the same climate zone. The difference between compliance percent and EDR is simply the mathematical construct used behind the scenes in the modeling software and the inclusion of all energy end uses within EDR. CAHP participants may be familiar with the EDR already as it’s being used for program compliance with the 2016-Code program.
Calculations for the EDR are currently available in CBECC-Res 2016 and EnergyPro 7. Instructions to activate and surface the EDR calculations can be found here. And Delta-EDR, the difference between a proposed home’s EDR and the prescriptive-home EDR, is the basis for eligibility with the California Advanced Homes Program’s 2016-Code offering.
However, it’s critical to note that the EDR when calculated using 2016-Code software uses 2016-Code TDV multipliers and modeling algorithms. It can’t be used to determine 2019-Code compliance or to predict what the EDR of a home will be under 2019-Code calculations. For those, a user must test the home using 2019-Code CBECC-Res beta software. See this CAHP factsheet for instructions on 2019-code beta software setup and testing. The 2019-Code beta software (CBECC-Res 2019) calculates the EDR automatically, as the primary demonstration of code compliance.
For the full write up, follow this link.