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The American Society of Heating, Refrigerating, & Air Conditioning Engineers (ASHRAE) publishes a well-recognized series of standards and guidelines relating to HVAC systems and issues. Often referenced in building codes, these standards are useful to consulting engineers, mechanical contractors, architects, and government agencies.

Standard 90.1 has been a benchmark for commercial building energy codes in the United States and a key basis for codes and standards around the world for more than 35 years.  It provides the minimum requirements for energy-efficient design of most buildings, except low-rise residential buildings.  Requirements are grouped into the following sections:

  1. Building envelope: wall insulation, roof insulation, roof reflectance, and glazing performance
  2. HVAC: equipment efficiency, system features, limitation on reheat and fan power
  3. Domestic hot water: equipment efficiency and system features
  4. Power: transformer efficiency, automatic controls, and energy monitoring
  5. Lighting: indoor lighting power density, lighting controls, exterior lighting, and parking garage lighting
  6. Other equipment: electric motors, potable water booster pumps, elevators and escalators
ASHRAE 90.1 2010 standards are expected to be adopted in Fall 2014. These new guidelines will provide energy savings of 25%, compared to 2004. Much of the savings comes from the Building Envelope section which now covers skylights, solar reflectance, and thermal emittance as well as new minimum efficiency requirements for HVAC equipment. 
Daylighting and lighting controls requirements, including those for occupancy and vacancy controls, exterior lighting controls, and whole building shut-off, were added to the lighting systems section.  

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“[Standard 90.1] is an indispensable reference for engineers and other professionals involved in the design of buildings and building systems.”

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