ATLANTA, GA — The American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE) has proposed an addendum designed to help building owners and consultants find clear specifications for interoperable BACnet systems more easily. ANSI/ASHRAE Standard 135-1995, BACnet — A Data Communication Protocol for Building Automation and Control Networks — is the only open, consensus-developed standard in the building controls industry.

According to ASHRAE, the proposed addendum “d” will replace the Conformance Class and Functional Group structure of the current standard with a new approach based on BACnet Interoperability Building Blocks (BIBB’s). The BIBB’s are grouped into the five areas: data sharing, alarm and event management, scheduling, trending, and device and network management.

The addendum is open for public review until Jan. 30, 2001. Drafts of the proposed addendum are available during public review period, and can be obtained online at

Publication date: 01/08/2001