New! Get more out of ASHRAE Standard 90.1 with a new online portal.

Once purchased, users can personalize their experience to access up-to-date Standard 90.1 resources in one consolidated location. Features of the portal include:

• A multi-publication online tool that enables users to view each publication side by side or separately, as well as copy, paste, print or annotate content as needed.
• The ability to view official ASHRAE Interpretations in the context where they matter.
• Access to Standard 90.1 User's Manual, which provides detailed instruction for design of commercial and high-rise residential buildings to ensure standard compliance. The user's manual also includes measurements and calculations in both I-P and SI units, sample calculations, application examples, forms to demonstrate compliance, and references to related resources and websites.
• A redlined version of Standard 90.1 showing what changes were made from the previous edition.

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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. This standard provides the minimum requirements for energy-efficient design of most buildings, except low-rise residential buildings. It offers, in detail, the minimum energy efficiency requirements for design and construction of new buildings and their systems, new portions of buildings and their systems, and new systems and equipment in existing buildings, as well as criteria for determining compliance with these requirements. It is an indispensable reference for engineers and other professionals involved in design of buildings and building systems.

This 2016 edition comprises numerous energy-saving measures and incorporates changes from more than 125 addenda. It also includes the following:

Format changes to improve usability and readability:

• One-column format for easier reading
• Exceptions separated, indented, and set apart with a smaller font size
• Italicized defined terms
• Changes to table formats to provide contrast between rows

Structural changes:

• A new Reference Standard Reproduction Annex 1 is provided at the end of the document. Section 5.1.4 now cites ASHRAE Standard 169 as the source for climatic data, and Annex 1 contains extracts of tables and figures from that standard for the reader’s convenience.
• Two new climate zones (0A/B) have been added to all prescriptive requirements tables.

Significant technical content changes:

Building Envelope

• Envelope verification in support of reduced air infiltration and increased requirements for air leakage of overhead coiling doors.
• Increased stringency requirements for metal building roofs and walls, fenestration, and opaque doors.
• Improved clarity on defining exterior walls, building orientation, fault assumptions for the effective R-value of air spaces, and calculation procedures for insulating metal building walls.

Lighting

• Modified requirements for exterior and interior lighting power densities to reflect new lighting levels in the IES Lighting Handbook.
• Modified requirements for lighting control to add additional controls in some space types and options to others to allow easier application of advanced controls.

Mechanical

• Large, electrically driven chilled-water plants are now required to be monitored for electric energy use and efficiency.
• Dedicated outdoor air systems now include both efficiency and rating requirements for compliance.
• Requirements are introduced for designs to include both use category and efficiency class.
• Requirement that air-cooled DX cooling units with economizers have a monitoring system to determine that the air economizer is working properly.

Energy Cost Budget (ECB) and Modeling

• Appendix G now can be used as a path for compliance with the standard.
• Changes to elevator, motor, and refrigeration baselines; changes to the baseline for existing building projects; and changes to specific opaque assemblies for the baseline envelope model. Modeling rule changes were made to heat pump auxiliary heat, economizer shutoff, lighting controls, humidification systems, cooling towers, and the simulation of preheat coils.