Addenda are substantive changes and additions to the BACnet Standard. Addenda go through a rigorous process including technical review, public review, formal answers to comments, and formal committee voting before publication. Once published, addenda are officially part of the BACnet Standard even though they are not in the same document. Each revision of the BACnet Standard document incorporates addenda from the prior version.
Any addenda currently out for public review can be found here.
The experiences of users and implementers of BACnet have led to many constructive suggestions for improving the original standard, ANSI/ASHRAE 135-1995 and, more recently, its successors, ANSI/ASHRAE 135-2001, 135-2004, 135-2008, 135-2010, 135-2012 and 135-2016. The same can also be said about ANSI/ASHRAE 135.1-2003, the companion standard for BACnet conformance testing, and its subsequent updates in 2007, 2009, 2011, 2013 and 2019.
PDF copies of all Addenda, sorted by year, are available for download below. To comment on public review drafts during the listed comment period obtain the necessary forms and instructions on the ASHRAE Website.
Please note this Page was last updated on January 5, 2020 and is believed to be current as of that date.
Addenda Overview
ASHRAE 135.1 –The BACnet Companion Standard
- Dowload PDF (This addendum is final and was approved by ASHRAE on May 31, 2018 and by the American National Standards Institute on June 1, 2018.)
- Add Property_List property tests
- Add tests for DUPLICATE_ENTRY error code
- Dowload PDF (This addendum is final and was approved by ASHRAE and by the American National Standards Institute on December 7, 2018.)
- Update alarm and event tests for protocol revisions 13 and higher
- Dowload PDF (This addendum is final and was approved by ASHRAE on May 31, 2018 and by the American National Standards Institute on June 1, 2018.)
- Fix the EPICS Consistency Tests
- Remove EPICS Database Templates
- Add Test for Use of Error Code BUSY with Command Object
- Dowload PDF (This addendum is final and was approved by ASHRAE on December 30, 2014 and by the American National Standards Institute on December 31, 2014.)
- Align SubscribeCOVProperty error codes with SubscribeCOV
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on January 21, 2012; by the ASHRAE Board of Directors on January 25, 2012; and by the American National Standards Institute on January 26, 2012.)
- Restrict The "Non-Documented" Test To Standard Object Types
- Add Router Binding Test
- Update Priority_For_Writing Tests
- Make Trend Log Tests Generic
- Bring Attention To Change In Length Of BACnetLogStatus
- Clarify That "Ignore Remote Packets" Test is Not for Use with Intervening Router
- Modify B/IP Test For NAT Operation
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on October 2, 2012; by the ASHRAE Board of Directors on October 26, 2012; and by the American National Standards Institute on October 27, 2012.)
- Add Network Priority Test
- Add Virtual Router Tests
- Replace Time Master Tests
- Add Backup and Restore Tests
- Add APDU Retry Test
- Add Workstation Schedule Interaction Tests
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on January 21, 2012; by the ASHRAE Board of Directors on January 25, 2012; and by the American National Standards Institute on January 26, 2012.)
- Generalize the Notify_Type Test
- Add in a Test for Resizable Array Properties
- Correct the Usage of VERIFY vs. CHECK in the Record_Count Test
- Correct the Trend Log COV Subscription Failure Test
- Remove the Testing Requirement That Status_Flags be Changeable
- Allow WritePropertyMultiple Tests to be Applied to Array Properties
- Modify Event Notifications Tests to Allow Use of Event Enrollment Objects
- Add a Test for Acknowledging Offnormal Events
- Update Expected Error Codes Negative COV Tests
- Correct the Use of WAIT vs. BEFORE in COV Notification Tests
- Improve Reading Multiple Properties with Multiple Embedded Access Errors Test
- Expand Allowable Errors for Older Product When Reading Array Properties
- Improve the Basic DeviceCommunicationControl Tests
- Add Alarm Summarization Tests
- Add Event Log Tests
- Add Structured View Tests
- Correct AddListElement Test
- Add ReadRange Test
- Remove Reliance on EPICS from DCC Test
- Add Who-Has Tests
- Correct Unknown Network Layer Message Type For Someone Else Test
- Clarify TRANSMIT And RECEIVE Addressing Information
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on October 2, 2012; by the ASHRAE Board of Directors on October 26, 2012; and by the American National Standards Institute on October 27, 2012.)
- Manual MS/TP Tests
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on June 23, 2012; by the ASHRAE Board of Directors on June 27, 2012; and by the American National Standards Institute on June 28, 2012.)
- Improve the Read All Properties Test
- Improve the Write Support Test
- Improve the Command Prioritization Test
- Clarify the Application of the Event_Enable Test
- Improve the Limit_Enable Test
- Update the Calendar Test
- Update Notification Class Tests to use UTCTimeSynchronization
- Update Schedule Tests to use UTCTimeSynchronization
- Add Protocol Revision 4 Schedule Object Tests
- Revise Stop_When_Full Test
- Make the Start_Time Test Generic
- Make the Log_Interval Test Generic
- Make the Buffer_Size Test Generic
- Correct the Record_Count Test
- Correct the Notification_Threshold Test
- Add Trigger Verification Tests
- Update BUFFER_READY Tests
- Add COV Subscription Lifetime Value Range Tests
- Modify List Management Test
- Implement COV Testing By Datatype
- Download PDF (This addendum was approved by the ASHRAE Standards Committee on January 21, 2006; by the ASHRAE Board of Directors on January 26, 2006; and by the American National Standards Institute on January 27, 2006.)
- Add Partial Day Scheduling to the Schedule object
- Enable reporting of proprietary events by the Event Enrollment object
- Allow detailed error reporting when all ReadPropertyMultiple accesses fail
- Remove the Recipient property from the Event Enrollment object
- MS/TP slave proxy tests
- Add a new silenced mode to the DeviceCommunicationControl service
- Addition of tests for Data Sharing BIBBs
- Specify the behavior of a BACnetARRAY when its size is changed
- Clarifying the behavior of a BACnet router when it receives an unknown network message type
- Testing unsupported service request execution
- Reading entire arrays
- Update negative tests
- Download PDF (This addendum was approved by the ASHRAE Standards Committee on June 23, 2007; by the ASHRAE Board of Directors on June 27, 2007; and by the American National Standards Institute on June 28, 2007.)
- Update references to refer to 135-2004
- Add new object types from 135-2004
- Omit certain tests based on Protocol_Revision
- Exception schedule priority requirements
- Minor corrections
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on January 29, 2011; by the ASHRAE Board of Directors on February 2, 2011; and by the American National Standards Institute on February 3, 2011.)
- Correct Test Step Indention
- Remove Recipient Test
- Correct Errors in Routing Tests
- Change the Ignore Process ID Test
- Add Test for Device Identifier Recipients
- Add Test for Network Address Recipients
- Add Tests for Disable Initiation
- Change Tests for Out_Of_Service, Status_Flags, and Reliability
- Add Tests for Non-router Network Layer Messages
- Remove Time Delay in TO-FAULT Tests
- Make Additions to the TCSL Language
- Change Acknowledge Alarm Initiation Tests
- Add New Tests for Reading and Presenting Properties
- Add New Event Notification Tests
- Update Trending Tests for Revision 3
- Add New Tests for Revision 4 Schedules
- Add New Test for Event Notification Network Priority
- Add Device and Network Mapping Tests
- Add Device Restart Notification Tests
- Add Schedule Written Datatypes Tests
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on June 26, 2010; by the ASHRAE Board of Directors on June 30, 2010; and by the American National Standards Institute on July 1, 2010.)
- Add test to verify that COV subscription lifetimes are not affected by time-sync requests
- Add new Active_COV_Subscription tests
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on January 29, 2011; by the ASHRAE Board of Directors on February 2, 2011; and by the American National Standards Institute on February 3, 2011.)
- Revise BACnet/IP tests
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on January 29, 2011; by the ASHRAE Board of Directors on February 2, 2011; and by the American National Standards Institute on February 3, 2011.)
- Clarify Tests for Ack Notification Timestamps
- Add new Database_Revision tests
- Update CreateObject Service Tests
- Update DeleteObject Service Tests
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on January 29, 2011; by the ASHRAE Board of Directors on February 2, 2011; and by the American National Standards Institute on February 3, 2011.)
- Change GetEventInformation Chaining Tests
- Change CHANGE_OF_STATE Test for Event Enrollment Object
- Change ConfirmedCOVEventNotification Service Initiation Tests to Non-infinite Lifetimes
- Change intrinsic tests for Event Enrollment Object
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on January 29, 2011; by the ASHRAE Board of Directors on February 2, 2011; and by the American National Standards Institute on February 3, 2011.)
- Improve Schedule Object Restoration Tests
- Add Test to Check Range of the Present_Value of Multi-state Objects
- Add Test for SubscribeCOV Service Execution Without a Lifetime Parameter
- Update Test for Processing of ReadProperty Service Responses
- Add Tests for Processing of GetEventInformation Service Responses
- Add Tests for Fallback from ReadPropertyMultiple to ReadProperty
- Allow Priorities in WriteProperty and WritePropertyMultiple Tests
- Add Test for Writing Array Size
- Clarify Test for Writing with a Value that is Out of Range
- Update Test for Writing with an Invalid Datatype
- Relax ReadPropertyMultiple Error Test
- Add Test for Unicast Who-Is
- Revise Unknown Network Layer Message Test
- Add New Trend Log Tests
- Add Event_Type Test
- Revise DeviceCommunicationControl Test
- Add Alarm Re-acknowledgement Tests
- Modify I-Am Tests
- Add A-side Trend Tests
- Make the EPICS Definition Generic
- Clarify Priority in the GetEnrollmentSummary Priority Filter Test
- Add Non-documented Property and Read-Only Property Tests
- Dowload PDF (This addendum is final and was approved by the ASHRAE Standards Committee on June 20, 2009; by the ASHRAE Board of Directors on June 24, 2009; and by the American National Standards Institute on June 25, 2009.)
- Omit certain tests when Averaging and Command properties are fixed or not present
- Accommodate Group objects whose members list is not changeable
- Revise Alarm Acknowledgement tests
- Add new Alarm Acknowledgement "offnormal" tests
- Label conditionally-writable properties in the EPICS
- Add new object types