EnergyGauge was built from the ground up as a sophisticated yet approachable home energy simulation tool, combining detailed DOE-2.1E-based hour-by-hour modeling with code-compliance reporting for the Florida Building Code and other climate zones across the U.S. The SizePro versions layer in ACCA-approved Manual J 8th Edition load calculations, including whole-house and room-by-room (zoned) heating and cooling loads, so HVAC contractors can size equipment accurately rather than relying on rules of thumb.
Beyond Manual J, ResSizePro performs Manual S system selection against a manufacturer equipment database and Manual D duct sizing for supply and return runs, producing the ANSI/RESNET/ACCA 310 HVAC Design Report that many jurisdictions and utility programs now require. The software is embedded in Kwik Model 3D as the loads engine, which lets designers sketch a 3D home and push geometry into EnergyGauge for rigorous load and energy analysis.
Developed and supported by a university research institute rather than a for-profit vendor, EnergyGauge has earned a reputation among raters and energy-focused HVAC contractors for defensible, peer-reviewed calculations. FSEC has historically offered complimentary licenses during extended transition periods, making it one of the more accessible rigorous Manual J/S/D tools for small HVAC shops doing high-performance homes.