

The two performance-based approaches in Standard 90.1 are the Energy Cost Budget (ECB) method found in Section 11 and the Performance Rating Method (PRM), commonly referred to by its location in the Standard, Appendix G.The prescriptive path establishes criteria for energy related characteristics of individual building components such as minimum R-values of insulation, maximum U-factors and solar heat gain coefficients of fenestration, maximum lighting power allowance, occupancy sensor requirements for lighting control, and economizer requirements for HVAC systems.


Commercial building energy codes such as ASHRAE Standard 90.1 typically include two types of approaches for demonstrating compliance prescriptive and performance paths.
