CBECC

CBECC from the California Energy Commission checks compliance with the Title 24 energy code for commercial and multifamily residential buildings. You build the model in a graphical interface, and the program runs an EnergyPlus simulation, compares it with a reference building and produces official compliance reports. Suited to energy consultants, architects and HVAC engineers. Limitations: it runs on Windows, and its rules are written for the California code — outside California it is mainly useful as an example and a learning tool.