Energy Design Rating

The software can calculate an energy design rating (EDR) as required in the CALGreen energy provisions (Title 24, Part 11). The EDR implementation is limited to newly constructed single- and multi-family dwellings.

The EDR is an alternate way to express the energy performance of a home using a scoring system where 100 represents the energy performance of a reference design building meeting the envelope requirements of the 2006 International Energy Conservation Code (IECC). The EDR is similar to the energy rating index in the 2015 IECC and the 2014 Residential Energy Services Network (RESNET) standard. Combining high levels of energy efficiency with generating renewable energy, a score of zero or less can be achieved.

Buildings complying with the current Building Energy Efficiency Standards are more efficient than the 2006 IECC, so most newly constructed buildings will have EDR scores below 100. Buildings with renewable generation like photovoltaics (PV) can achieve a negative score. If an EDR is calculated for an older inefficient home, the score would likely be well over 100.

When the user requests an EDR calculation, additional inputs are required specifying more details about PV systems, and an EDR screen is displayed at the end of a calculation and reported on the CF1R. EDR PV inputs and calculations are not used for compliance with the Title 24, Part 6.