Color
Book a demo
Glossary
Energy standards and regulation

What is ASHRAE 90.1?

Definition

ASHRAE 90.1 is the energy standard for buildings except low-rise residential, published by ASHRAE with IES. It sets minimum requirements for the building envelope, HVAC, service water heating, power, lighting and controls, and it is referenced by most US commercial energy codes.

What it is

ASHRAE 90.1, formally ANSI/ASHRAE/IES Standard 90.1, defines minimum energy efficiency requirements for the design of new buildings, additions and major alterations. It is updated on a regular cycle, and each edition tightens requirements.

Projects can comply through mandatory provisions plus a prescriptive path, or through performance paths such as the Energy Cost Budget method or the Performance Rating Method in Appendix G. Controls requirements cover items such as automatic shutoff, setpoint and schedule control, and demand-controlled ventilation in certain spaces.

Who it applies to / where it is used

The standard is used by architects, MEP engineers and code officials in states and cities that adopt it, often through the commercial provisions of their energy code. Federal buildings and green building rating systems such as LEED also reference it. Which edition applies depends on local adoption, so check the current local rule.

How it is measured / what evidence it needs

Compliance at design is shown through drawings, calculations and energy models. For existing buildings, the useful question is whether the controls the standard describes actually operate as intended.

  • Control sequences and schedules as designed and as operating
  • Setpoint and setback records by zone
  • Ventilation and demand-controlled ventilation behavior
  • Measured energy use against the design intent

How Aqueduct helps

Aqueduct reads the controls ASHRAE 90.1 describes and shows whether they behave in operation, then acts through them where control is enabled, with owner approval.

  • Schedule, setpoint and demand-control behavior tracked from BMS points over BACnet or Modbus
  • Fault detection when equipment runs outside its schedule or setpoints drift
  • Setpoint and schedule changes through aQ EnergySmart where control is enabled, with owner approval
  • Measured results verified at the meter after each change
Questions

ASHRAE 90.1: common questions

ASHRAE 90.1 covers the envelope, HVAC, service water heating, power, lighting and controls in buildings other than low-rise residential. It sets minimum efficiency requirements that energy codes adopt.

ASHRAE 90.1 is a standard. It becomes enforceable when a state or city adopts it, usually through its commercial energy code. The adopted edition varies by jurisdiction.

It applies to new construction, additions and alterations within its scope. Existing buildings are usually affected when they undergo renovation or system replacement.

Aqueduct reads the schedules, setpoints and demand controls the standard describes and flags when they drift in operation. Where control is enabled, with owner approval, it adjusts them and verifies the result at the meter.

See Aqueduct on your own facility.

Bring a site, a utility bill or a question. We will show you where the loss is.

Book a demo Talk to our team