Percent improvement over ASHRAE 90.1 is the basis for awarding energy points within the LEED Rating system.ĪSHRAE 90.1 is an industry standard referenced by the USGBC in the LEED building certification program.
Building designs will state their performance as "40% better than ASHRAE Standard 90.1-2007" or "20% better than ASHRAE 90.1-2010".
The performance approach is also used to demonstrate design energy efficiency, often expressed as percent better than ASHRAE Standard 90.1.
The proposed energy cost budget must be less than or equal to the baseline energy cost budget to achieve compliance.
A building energy simulation is then performed on the proposed building design.
The ECB is expressed in units of dollars. It is built according to the prescriptive requirements of ASHRAE 90.1 (section 5-10).
The building energy simulation is to model a building with the same size and program as the project building.
Performance Path - A proposed building design is demonstrated (through building energy simulation) to use less energy than a baseline building built to ASHRAE 90.1 specifications.
Other Equipment (Section 10): Electric motors, potable water booster pumps, elevators and escalators.
Prescriptive Path - All components of the building meet the minimum standards specified by ASHRAE 90.1. There are two means or paths for building designers to comply with ASHRAE 90.1 Even though this in an American standard, it is adopted across Canada as a standard in the construction industry. ASHRAE by definition is the American Society of Heating Refrigeration and Air-Conditioning and it is a US standard that provides minimum requirements for energy efficient designs for buildings except for low-rise residential buildings.