Addenda are substantive changes and additions to the BACnet Standard. They 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 to the prior version.
The experiences of users and implementers of BACnet have led to many constructive suggestions for improving the standard. The same can also be said about the companion standard for BACnet conformance testing. These updates are frequently issued as addenda so they can be made available without waiting for the next release of the full standard.
PDF copies of all published addenda are available for download below and on the ASHRAE website.
To comment on addenda currently out for public review, obtain the necessary forms and instructions on the ASHRAE website. The addenda can be found here.
Please note this page was last updated on May 10, 2024, and is believed to be current as of that date.
Addenda Overview
ASHRAE 135 – The BACnet Standard
- Addenda to BACnet-2020
- Addenda to BACnet-2016
- Addenda to BACnet-2012
- Addenda to BACnet-2010
- Addenda to BACnet-2008
- Addenda to BACnet-2004
- Addenda to BACnet-2001
- Addenda to BACnet-1995
ASHRAE 135.1 –The BACnet Companion Standard
- Addenda to BACnet 135.1-2019
- Addenda to BACnet-135.1-2013
- Addenda to BACnet 135.1-2011
- Addenda to BACnet 135.1-2009
- Addenda to BACnet 135.1-2007
- Addenda to BACnet 135.1-2003
(Approved by ASHRAE on June 28, 2024; and by the American National Standards Institute on June 28, 2024.)
1. Certificate Authority Requirements Interchange File Format
(Approved by the ASHRAE Standards Committee on June 28, 2024, and by the American National Standards Institute on June 28, 2024.)
1. Changes to Clause 5 to correct segmentation errors.
(Approved by the ASHRAE Standards Committee on June 28, 2024, and by the American National Standards Institute on June 28, 2024.)
1. Add missing formal definitions of ASN.1 datatypes
(Approved by ASHRAE on June 28, 2024; and by the American National Standards Institute on June 28, 2024.)
1. Define a new “short form” for Array, List, and SequenceOf base types.
2. Formally define the existing “short form” for primitives.
(Approved by ASHRAE on June 28, 2024; and by the American National Standards Institute on June 28, 2024.)
1. Clarify Engineering Units
(Approved by ASHRAE and the American National Standards Institute on November 30, 2022.)
- Formal Definition of the 'data_attributes' Parameter, p.3.
- Redefinition of 'Must Understand' for data options, p.4.
- Changes to segmentation to enforce data attribute consistency, p. 6.
(Approved by ASHRAE and the American National Standards Institute on January 21, 2022.)
- MS/TP Language Replacement, p. 3.
- CSML Name Aliasing, p.38
- Remove writableWhen and requiredWhen, p. 40.
(Approved by ASHRAE and the American National Standards Institute on January 21, 2022.)
- Update the Network Port Object and Add BACnet/SC Configuration Support, p.3
- Modifications to Annex AB, p.38
- Add a Procedure to Replace BACnet/SC Certificates, p.40
- Add Network Port Object Configuration BIBBs, p.44
(Approved by ASHRAE and the American National Standards Institute on January 21, 2022.)
- Introduce the Concept of Color for BACnet, p. 3
- Add new Color object type, p. 4
- Add new Color Temperature object type, p. 11
- Add color-reference properties to LO and BLO object types, p.19
- Add Add high/low trim to LO object type, p. 23
- Aggregated changes to Clause 21 and 25, p. 26
- BIBB Changes to Support Additional Object Types, p. 29
(Approved by ASHRAE and the American National Standards Institute on January 21, 2022.)
- Add new property Write_Every_Scheduled_Action to the Schedule object, p. 3
- Fix XML namespace
(Approved by ASHRAE and the American National Standards Institute on August 31, 2021.)
- TLS V1.3 Cipher Suite Application Profile for BACnet/SC, p.3
This addendum isfinal and was approved by both ASHRAE and the American National Standards Institute on November 18, 2019.
- Add Who-Am-I and You-Are Services
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on November 18, 2019.
- Remove Clause 24, Network Security
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on November 18, 2019.
- Introduce BACnet Secure Connect Datalink Layer Option
- Introduce BACnet/SC in the Application and Network Layder Specifications
- Add new Annex YY for the BACnet Secure Connect Datalink Layer Option
- Add a Device_UUID Property to the Device Object
- Extend APDU Encoding for Large APDU Sizes
- New Error Codes for BACnet/SC
- Interoperability Specification Extensions for BACnet/SC
- Define Extended 6-Octet VMAC
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on August 26, 2019.
- Add Time Series Data Exchange Format
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on August 26, 2019.
- Introduce BACnetARRAY of BACnetLIST collection property data type
- Clarifications on character and value encoding issues.
- Clarify transmission of unconfirmed COV notifications.
- Clarify logging of event notifications.
- Clarify recording of status events in log buffers.
- Clarify Event Enrollment object reliability evaluation.
- Clarify the Global Group object reliability evaluation.
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on August 26, 2019.
- Add re-alert transitions to the CHANGE_OF_LIFE_SAFETY event algorithm.
- Add specific error codes for LifeSafetyOperation error situations.
- Add support for elevator-basedoccupant evacuation (OEO) to the life safety objects
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on August 26, 2019.
- Add Elevator BIBBs and Device Profiles
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on August 26, 2019.
- Add new engineering units.
- Add mandate to accept writes of NULL to non-commendable properties.
- Add intrinsic fault reporting to Lighting Output object type.
- Deprecate Time form of timestamps.
- Clarify the Multi-state object types when Number_Of_States shrinks
- Fix the language for event type and message text parameters of event notifications.
- Clarify the object instance 4194303.
- Wildcard instance for Network Port objects in ReadPropertyMultiple requests
- Clarify the timestamp of trend log and trend log multiple log records.
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Fix the Absentee_Limit property of the Access Credential object type.
- Ensure that the denied or granted access event is generated last.
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Make rules for POST consistent with rules for PUT.
- Make 'type' consistent at all levels and introduce 'effectiveType'
- Fully specify the behavior of "includes".
- Remove the path syntax from the 'select' query parameter.
- Resolve conflicting statements about configuring external authorization servers.
- Remove incorrect table for callback formats.
- Allow plain text POSTs for primitive data.
- Allow extended error numbers.
- Add new error numbers.
- Add formal definition for JSON equivalent to XML's.
- Specify 'name' safety check for setting data.
- Specify how to evaluate relative paths for collections of links.
- Allow proprietary categories for the 'metadata' query.
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Make SCHED BIBBs consistent on supported datatypes, and add BOOLEAN.
- Clarify COV- and COVP-related BIBBs.
- Clock is required for support of AE-ACK-A
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Reduce allowed ranges for Usage Timeout.
- Specify design choices for MS/TP devices.
- Handle unwanted MS/TP frames in IDLE state.
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Clarify Result(-) response for failed WritePropertyMultiple requests.
- Clarify ReadPropertyMultiple response on OPTIONAL when empty.
- Clarify Out-Of-Service
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Expands the reserved range of BACnet-PropertyIdentifier
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Add Audit Reporting
- Change DeviceCommunicationControl Service for Audit Reporting
- Modify Logging Objects to Allow for Extremely Large Logs
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Add Lighting BIBBs and Device Profiles
This addendum is final and was approved by both ASHRAE and the American National Standards Institute on June 15, 2018.
- Add a Staging Object Type
This addendum is final and was approved by ASHRAE on April 29, 2016 and by the American National Standards Institute on April 29, 2016.
- Extend BIBBs for Primitive Value Objects
- Add New BIBBs for Event Enrollment and Subscription
- Amend B-AWS Related BIBBs for Revised Event Reporting
- Add Life Safety BIBBs and Device Profiles
- Add Physical Access Control BIBBs and Device Profiles
- Add an All-Domain Advanced Workstation Profile
This addendum is final and was approved by ASHRAE on April 29, 2016 and by the American National Standards Institute on April 29, 2016.
- Add CSML Descriptions of BACnet Devices
- Add Semantic Tags to All Objects
- Extend Structured View Object to Contain Semantic Information
- Change Clause 21 identifiers to use a consistent format.
- Add Data Revisioning Capabilities to CSML
This addendum is final and was approved by ASHRAE on April 29, 2016 and by the American National Standards Institute on April 29, 2016.
- Extend BACnet/WS with RESTful services for complex data types and subscriptions.
- Extract data model from Annex Q into separate common model
- Rework Annex Q to be an XML syntax for the common model.
- Add a JSON syntax for the common model.
- Replace Annex N SOAP services and add a migration guide.
- Change Clause 21 identifiers to use a consistent format.
This addendum is final and was approved by ASHRAE on February 29, 2016 and by the American National Standards Institute on March 1, 2016.
- Correct Application State Machine Failover
- Increase Segmentation Window Size for MS/TP
(This addendum is final and was approved by ASHRAE on February 29, 2016 and by the American National Standards Institute on March 1, 2016.)
- Add engineering units
- Harmonize message text handling for all alarm services
- Ensure Alert Enrollment objects do not send notifications which require acknowledgment
- Allow selection of the Nth last day of the month in a BACnetWeekNDay
- Remove initiation of GetEnrollmentSummary from AE-AS-A
- Ensure UTC_Offset is configurable
- Clarify ReadRange
- Clarify the effect of changing Buffer_Size
- Stop MS/TP nodes from sending POLL_FOR_MASTER frames to themselves
- Improve the Clause 12 preamble
- Fix the Notification_Class property of the Notification Class object
This addendum is final and was approved by ASHRAE on February 29, 2016 and by the American National Standards Institute on March 1, 2016.
- Advanced Network Configuration
- BVLL Responses for non-BBMD Devices
This addendum is final and was approved by ASHRAE on February 29, 2016 and by the American National Standards Institute on March 1, 2016.
- Add Elevator Object Types
- Add COV Property Multiple Services
- Add a New Fault Algorithm FAULT_LISTED
This addendum is final and was approved by ASHRAE on February 29, 2016 and by the American National Standards Institute on March 1, 2016.
- Add support for IPv6
- Add an additional method for VMAC determination.
This addendum is final and was approved by ASHRAE on December 30, 2014 and by the American National Standards Institute on December 31, 2014.
- Add a Timer Object
- Correct Expiry_Time property name to Expiration_Time in the Access Credential Object
This addendum is final and was approved by ASHRAE on December 30, 2014 and by the American National Standards Institute on December 31, 2014.
- Add Value Source Information
This addendum is final and was approved by ASHRAE on December 30, 2014 and by the American National Standards Institute on December 31, 2014.
- Add Network Port Object Type
- Changes to Annex J for the Network Port Object
- Changes to 135-2012al for the Network Port Object
This addendum is final and was approved by the ASHRAE Standards Committee on June 28, 2014; by the ASHRAE Board of Directors on July 2, 2014; and by the American National Standards Institute on July 3, 2014.
- Add Binary Lighting Output Object Type
- Setting Non-zero Values to Change_Of_State_Count and Elapsed_Active_Time
This addendum is final and was approved by the ASHRAE Standards Committee on June 28, 2014; by the ASHRAE Board of Directors on July 2, 2014; and by the American National Standards Institute on July 3, 2014.
- Remove Incorrect Recipient_ListRequirement to be Non-empty.
- Section Removed
- Extend the Allowable BACnetPropertyStates Enumeration Range
- Specifically Disallow Duplicate Time Entries in Schedules
- Non-BBMD Responses to BBMD BVLL Requests
This addendum is final and was approved by the ASHRAE Standards Committee on June 28, 2014; by the ASHRAE Board of Directors on July 2, 2014; and by the American National Standards Institute on July 3, 2014.
- Extend the CHANGE_OF_STATE Event Algorithm for All Discrete Types
- Add a New Event Algorithm CHANGE_OF_DISCRETE_VALUE
- Add a New Fault Algorithm FAULT_OUT_OF_RANGE
- Extend the Loop Object Type to Support Specific Low and High Error Limits
- Add the Ability to Report Faults to Date and Time Related Value Objects
- Add the Ability to Report Faults to the Command, Device, and Notification Class Objects
This addendum is final and was approved by the ASHRAE Standards Committee on June 28, 2014; by the ASHRAE Board of Directors on July 2, 2014; and by the American National Standards Institute on July 3, 2014.
- Deprecate Execution of GetAlarmSummary
- Deprecate Execution of GetEnrollmentSummary
2012auThis addendum is final and was approved by the ASHRAE Standards Committee on June 28, 2014; by the ASHRAE Board of Directors on July 2, 2014; and by the American National Standards Institute on July 3, 2014.
- Clarify Authentication Factor Value Encoding Rules
- Clarify Coercion Support Requirements
This addendum is final and was approved by the ASHRAE Standards Committee on June 28, 2014; by the ASHRAE Board of Directors on July 2, 2014; and by the American National Standards Institute on July 3, 2014.
- Add Interface_Value Property
This addendum is final and was approved by the ASHRAE Standards Committee on June 28, 2014; by the ASHRAE Board of Directors on July 2, 2014; and by the American National Standards Institute on July 3, 2014.
- Add Extended Length MS/TP Frames
- Add Procedure for Determining Maximum Conveyable APDU
This addendum is final and was approved by ASHRAE on December 30, 2014 and by the American National Standards Institute on December 31, 2014.
- Specify Best Practices for Gateway Design
- Add new BIBBS and Devices Profiles
(This addendum is final and was approved by the ASHRAE Standards Committee on January 26, 2013; by the ASHRAE Board of Directors on January 30, 2013; and by the American National Standards Institute on January 30, 2013.)
- Add New Engineering Units
- Clarify Coercion Requirements
- Specify SubscribeCOVProperty Error Codes
- Add Slave Proxy BIBBs
- Allow Unicast I-Have messages
- Require Both Time Sync Services for Time Masters
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.
- Define new Lighting Output object type.
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.
- Update ReadRange Example
- Add Present Value Range to Value Objects
- Clarify Reject-Message-To-Network reason #3 DNET
- Prevent Reliance on Static Router Bindings
- Add Property_List Property
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.
- Specify Address Range Requirements
- Specify 'abort-reason' Values.
- Add Serial_Number Property
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 July 26, 2012.
- Add Channel Object Type
- Add WriteGroup Service
This addendum is final and was approved by the ASHRAE Standards Committee on June 25, 2011; by the ASHRAE Board of Directors on June 29, 2011; and by the American National Standards Institute on June 30, 2011.
- Remove Annex C and Annex D
- Clarify Optionality of Properties Related to Intrinsic Event Reporting
- Clarify Optionality of Properties Related to Change of Value Reporting
- Ensure that Pulse_Rate and Limit_Monitoring_Interval are Always Together.
- Clarify when Priority_Array and Relinquish_Default are allowed to be Present
- Clarify when Segmentation Related Properties are Allowed to be Present.
- Clarify when Virtual Terminal Related Properties are Allowed to be Present.
- Clarify when Time Synchronization Interval Properties are Allowed to be Present.
- Clarify when Backup and Restore Properties are Allowed to be Present.
- Clarify when the Active_COV_Subscriptions Property is Allowed to be Present.
- Clarify when the Slave Proxy Properties are Allowed to be Present.
- Clarify when the Restart Related Properties are Allowed to be Present.
- Clarify when the Log_DeviceObjectProperty Property is Allowed to be Present.
- Clarify when the Clock Aligning Properties are Allowed to be Present.
- Clarify when the Occupancy Counting Properties are Allowed to be Present.
- Add the Ability to Configure Event Message Text
- Add an Event Detection Enable / Disable Property
- Add the Ability to Dynamically Suppress Event Detection
- Add the Ability to Specify a Different Time Delay for TO-NORMAL Transitions
- Add the Ability to Inhibit the Evaluation of Fault Conditions
- Separate the Detection of Fault Conditions from Intrinsic Reporting
- This section removed after the first public review.
- Ensure that Event Notifications are not Ignored due to Character Set Issues
- Make the Event Reporting Property Descriptions Consistent
- Identify the Property in each Object that is Monitored by Intrinsic Reporting
- Change the Description of the Reliability Property
- Improve Fault Detection in Event Enrollment Objects
- Add the Ability for some Objects Types to Send Only Fault Notifications
- Add a Notification Forwarder Object Type
- Reduce the Requirements on Notification-Servers
- Add an Alert Enrollment Object Type
- Improve the Specification of Event Reporting
This addendum is final and was approved by the ASHRAE Standards Committee on June 25, 2011; by the ASHRAE Board of Directors on June 29, 2011; and by the American National Standards Institute on June 30, 2011.
- Add a "Too large" error condition to the ERROR authentication encoding.
- Simplify the Initialization of Negative and Positive Access Rules
- Replace Master_Exemption Property of the Access Credential Object Type
- Add Fault Enumeration to Door_Status in Access Door Object Type
- Clarify the behavior of Door_Unlock_Delay_Time and Present_Value of Access Door
This addendum is final and was approved by the ASHRAE Standards Committee on June 25, 2011; by the ASHRAE Board of Directors on June 29, 2011; and by the American National Standards Institute on June 30, 2011.
- This section was removed.
- Provide Examples of Encoding Tag Numbers Greater than 14.
- Allow Feedback_Value to be used to calculate Elapsed_Active_Time
- Add READ_ACCESS_DENIED condition to ReadProperty and ReadPropertyMultiple
- Remove Unqualified Frame Reference in USE_TOKEN
- Align the Loop Object's Out_Of_Service Behavior with Other Objects
- Add DM-DDB-A to the Device Profile B-AAC
- This section was removed after the first public review.
- Clarify Requirements for BBMDs
- Restrict BBMD Foreign Device Forwarding
- Restrict ReadRange 'Count' to INTEGER16
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 March 3, 2011.
- Remove ReadPropertyConditional
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.
- Prevent BBMD Broadcast Storms
- Align BIBBs for Automated Trend Retrieval
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 the Usage of Dates and Times
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.
- Add More Standard Baud Rates for MS/TP
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 Event_Message_Texts
- Add UnconfirmedEventNotification to Automated Trend Retrieval BIBBs
- Modify MS/TP State Machine to Ignore Data Not For Us
- Add New Engineering Units5.Add Duplicate Segment Detection
(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 a new Global Group object type
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.
- Update BACnet Network Security
This addendum is final and was approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28, 2010.
- Specify Deployment Options for MS/TP
This addendum is final andwas approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28, 2010.
- Fix the Criteria for COV for Load Control
- Clarify Trend Log Time Stamp
- Clarify ReadRange on Lists
- Clarify Results of Using Special Property Identifiers
This addendum is final and was approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28, 2010.
- Add more primitive value objects.
This addendum is final and was approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28, 2010.
- Clarify the use of RejectPDU
- .Add error code UNSUPPORTED_OBJECT_TYPE for CreateObject service
- Add new Abort and Error codes
- Specify proper Errors when attempting access to the Log_Buffer property
This addendum is final and was approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28, 2010.) A new standard way of representing building data will give BACnet new capabilities for standardized communications between a wide range of applications. A definition for an XML syntax which can be used to represent building data in a consistent, flexible and extensiblemanner is defined by this addendumin the form of a new annex to the standard. The Extensible Markup Language (XML) is a popular technology in the data processing and communications worlds due to its ability to model a wide range of data and its ability to be transformed and extended. With this new IT-friendly way of representing building data, BACnet will open up a range of possible new ways to share data. XML can be used for exchanging files between systems, integrating buildings with energy utilities, and expanding enterprise integration with richer Web services. Some of these new applications will be standardized in future addenda to the standard based on the syntax defined here.
- XML Data Formats
This addendum is final and was approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28, 2010.
- Add support for long Backup and Restore preparation times.
This addendum is final and was approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28,2010.) Addendum 135-2008kadds support for one "Character Encoding Form" at a time, needed for interoperability. Also incorporates the Japanese Industrial Standard Committee's change from "JIS C 6226" to "JIS X 0208."
- Add support for UTF-82.Change JIS reference
This addendum is final and was approved by the ASHRAE Standards Committee on January 23, 2010; by the ASHRAE Board of Directors on January 27, 2010; and by the American National Standards Institute on January 28, 2010.
- Change Device_Busy to Busy and apply to the Command Object type
- Prevent overflow and underflow in Pulse_Converter object's Count property.
- Add context tags to Clause 21 production BACnetPropertyStates
- Add new BACnetEngineering Units.
- Define COV notification service Error returns.
- Remove non-support for automatic cancellation of COV subscriptions.
- (Add support for the UTF-8-characterset moved to Addendum k)
- Add even and odd day support in scheduling.
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.
- Fix the MS/TP TokenCount Value
- Clarify "Supported"
- Remove NM-CE-A from Device Profiles
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.
- Clarify the circumstances that cause the File object's Archive property to be set to TRUE or FALSE
- Require support for COV subscriptions of at least 8 hours' lifetime.
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.
- Clarify transitions in FLOATING_LIMIT and OUT_OF_RANGE events
- Clarify router action when a network is marked as temporarily unreachable.
- Clarify the destination MAC used when replying to a broadcast DER frame.
- Clarify the handling of write priorities greater than 16.
- Clarify LogDatum presentation
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.
- Accommodate remote operator access and NAT in Annex J BACnet/IP
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.) Addendum 135-2008ladds new operator workstation profiles and BIBBs.
- Add new workstation BIBBs and profiles.
- Here is the link to the 1st Publication Public Review Draft of Addendum 135-2004l.
- Here is the link to the 2nd Publication Public Review Draft of Addendum 135-2008l.
- Here is the link to the 3rd Publication Public Review Draft of Addendum 135-2008l.
This addendum is final and was approvedby 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.) The addendum defines physical access control extensions to BACnet. Although access control is part of the building automation system, in many ways it is more complex and has different constraints and requirements than typical HVAC control. In particular, there is a much greater emphasis on the security of the devices and the communications to those devices. Addendum 135-2004g provides a new BACnet security architecture to address these and other concerns.
- Add a new Access Point object type.
- Add a new Access Zone object type.
- Add a new Access User object type.
- Add a new Access Rights object type.
- Add a new Access Credential object type.
- Add a new Credential Data Input object type.
- Add a new Access ACCESS_EVENT event algorithm.
- Add a new Annex P BACnet encoding rules for authentication factor values.
This addendum is final and was approved by the ASHRAE Standards Committee on January 24, 2009; by the ASHRAE Board of Directors on January 28, 2009; and by the American National Standards Institute on January 29, 2009.
- Allow unicast I-Ams
- Define virtual addressing for data links with MAC addresses longer than 6 octets.
- Define the use of ZigBee as a BACnet data link layer.
(This addendum was approved for publication by the ASHRAE Board of Directors on October 24, 2008; and by the American National Standards Institute on October 27, 2008.) Addendum 135-2004m contains 12 independent changes to the BACnet standard, including: resolving Foreign Device registration period ambiguities, clarifying the GetEventEnrollment service's Priority Filter parameter, adding requirements to Alarm and Event BIBBs, and defining "object."
- Resolve Foreign Device registration grace period and remaining time ambiguities
- Improve Clause 5 FillWindow segment timeout constraints
- Clarify the Priority Filter parameter in the GetEventEnrollment service request
- Allow alarms to be re-acknowledged successfully
- Add requirements to Alarm and Event BIBBs
- Remove B-BC requirements for BIBBs without use cases
- Clarify that a device may support only the ReinitializeDevice restart choices
- Clarify DeviceCommunicationsControl and ReinitializeDevice interactions
- Define "object"
- Add a Deadband property to the Loop object
- Correct the TO-FAULT conditions in the Life Safety objects' Reliability properties
- Clarify the Trend Log's acquisition of Status_Flags
Here is the link to the 1st Publication Public Review Draft of Addendum 135-2004m.
This addendum was approved by ASHRAE Board of Directors on October 24, 2008 and by the American National Standards Institute on October 27, 2008.
- Add a new Event Log object type
- Add a new Global Group object type
- Add a new Trend Log Multiple object type
- Harmonize the Trend Log object with the new Event Log and Trend Log Multiple objects
- Define a means for a device to provide a notification that it has restarted.
- Define a means to configure a device to periodically send time synchronization messages.
- Extend the number of character sets supported.
- Enable devices other than alarm recipients to acknowledge alarms.
- Allow MS/TP BACnet Data Expecting Reply frames to be broadcast.
- Revise the Clause 5 state machines to handle slow servers.
- Add new Error Codes and specify usage.
- Add new Reliability enumeration to objects with a Reliability property.
- Here is the link to the 1st Publication Public Review Draft of Addendum 135-2004b.
- Here is the link to the 2nd Publication Public Review Draft of Addendum 135-2004b that contains contains only independent substantive changes made to the first public review draft and must be reviewed with that document.
- Here is the link to the 3rd Publication Public Review Draft of Addendum 135-2004b that contains contains only independent substantive changes made to the second public review draft and must be reviewed with that document.
This addendum wasapproved for publication by the ASHRAE Board of Directors on October 24, 2008; and by the American National Standards Institute on October 27, 2008.Addendum 135-2004mcontains 12 independent changes to the BACnet standard, including: resolving Foreign Device registration period ambiguities, clarifying the GetEventEnrollment service's Priority Filter parameter, adding requirements to Alarm and Event BIBBs, and defining "object."
- Resolve Foreign Device registration grace period and remaining time ambiguities.
- Improve Clause 5 FillWindow segment timeout constraints.
- Clarify the Priority Filter parameter in the GetEventEnrollment service request.
- Allow alarms to be re-acknowledged successfully.
- Add requirements to Alarm and Event BIBBs
- Remove B-BC requirements for BIBBs without use cases
- Clarify that a device may support only the ReinitializeDevice restart choices
- Clarify DeviceCommunicationsControl and ReinitializeDevice interactions
- Define "object"
- Add a Deadband property to the Loop object
- Correct the TO-FAULT conditions in the Life Safety objects' Reliability properties
- Clarify the Trend Log's acquisition of Status_Flags
This addendum was approved for publication by the ASHRAE Board of Directors March 25, 2007 and by the American National Standards Institute on March 26, 2007.
- Add a new Load Control object type
- Here is the link to the 1st Publication Public Review Draft of Addendum 135-2004e.
- Here is the link to the 2nd Publication Public Review Draft of Addendum 135-2004e that contains only independent substantive changes made to the first public review draft and must be reviewed with that document.
This addendum was approved for publication by the ASHRAE Board of Directors June 29, 2006 and by the American National Standards Institute on June 30, 2006.
- Add a new Structured View object type.
- Allow acknowledgement of unseen TO-OFFNORMAL event notifications.
- Relax the Private Transfer and Text Message BIBB requirements
- Exclude LIFE_SAFETY and BUFFER_READY notifications from the Alarm Notifications BIBBs
- Establish the minimum requirements for a BACnet device with an application layer.
- Remove the requirement for the DM-DOB-A BIBB from theB-OWS and B-BC device profiles.
- Relax mandated values for APDU timeouts and retries when configurable and change default values.
- Fix EventCount handling error in MS/TP Master Node State Machine
- Permit routers to use a local network number in Device_Address_Binding
- Identify conditionally writable properties.
- Specify Error returns for the AcknowledgeAlarm service.
This addendum was approved for publication by the ASHRAE Board of Directors September 29, 2006 and by the American National Standards Institute on October 2, 2006.
- Add BACnet/WS web services interface.
This addendum was approved for publication by the ASHRAE Board of Directors and by the American National Standards Institute on February 10, 2005.
- Revise Life Safety Point and Life Safety Zone objects to modify their behavior when placed out of service.
- Add clauses describing BACnet-EIB/KNX mapping
- Allow Life Safety objects to advertise supported mode
- Add Unsilence Options to the LifeSafetyOperation Service
- Specify the relationship between the Event_Type and Event_Parameter properties
- Add a new Accumulator Object Type
- Add a new Pulse Converter Object Type
- Standardize event notification priorities.
- Define Abort reason when insufficient segments are available.
- Add new Error Codes and specify usage.
- 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
- Add the capability to issue I-Am responses on behalf of MS/TP slave devices.
- Add a new silenced mode to the DeviceCommunicationControl service.
- Add 21 new engineering units.
- Specify the behavior of a BACnetArray when its size is changed.
- Clarify the behavior of a BACnet router when it receives an unknown network message type
- Remove UTC timestamps from Trend Logs and guarantee Trend Log record ordering
- Define the PTP connection status when the half-router can and cannot re-establish the connection.
- Add Object Profiles and Extensions
- Add the capability for devices to advertise the maximum number of segments of a segmented APDU that they can receive.
- Replace Clause 22 with a new clause entitled "Conformance and Interoperability”.
- Update Annex A, "Protocol Implementation Conformance Statement"
- Add a new Annex K entitled "BACnet Interoperability Building Blocks (BIBBs)"
- Add a new Annex L entitled "Descriptions and Profiles of Standardized BACnet Devices”.
- Add a new Life Safety Point object type that represents the characteristics of initiating and indicating devices in the fire, life safety, and security applications.
- Add a new Life Safety Zone object type that represents the characteristics associated with an arbitrary group of BACnet Life Safety Point and Life Safety Zone objects
- Add functionality to the existing BACnet alarm and event features needed to support the Life Safety Point and Life Safety Zone object types.
- Add a new LifeSafetyOperation service that provides silence and reset capabilities needed for life safety systems.
- Add a new sub-clause to 19 to describe the use of existing BACnet services to provide backup and restore capability.
- Define a new service, SubscribeCOVProperty, to allow COV notifications for arbitrary properties of an object with subscriber-specified COV increments.
- Add Vendor ID to proprietary MS/TP frames 8.Add a new service, GetEventInformation, that provides enough information to acknowledge alarms.
- Inconsistencies are eliminated in the definitions of the Analog and Binary Value object types.
- Any device that receives and executes UnconfirmedEventNotification service requests must support programmable process identifiers.
- Modify each event-generating object type to contain the last timestamp for each acknowledgeable transition.
- Modify the Notification Class object by requiring that the 'Notification Class' property be equivalent to the instance number of the Notification Class object.
- Modify the Event Notification services to make the 'To State' parameter mandatory for notifications of type ACK_NOTIFICATION.
- A new BACnetDeviceObjectPropertyReference production is added and its use in the Event Enrollment and Schedule object types is specified.
- Add a Multi-state Value object type.
- Add an Averaging object type.
- Change all 'Process Identifier' properties and parameters to Unsigned32.
- Change the Multi-state Input object type to correct flaws related to fault detection and reporting and achieve consistency with the proposed Multi-state Value object type.
- Add a Protocol_Revision property to the Device object type.
- The File object type is changed to allow truncation and partial deletion operations.
- A new ReadRange service is added to permit reading a range of data items from a property whose datatype is a list or array of lists.
- A new UTCTimeSynchronization service is introduced and related changes are made to properties in the Device object type.
- Add a Trend Log object type.
- The UnconfirmedCOVNotification service is extended to allow notifications without prior subscription as a means of distributing globally important data to a potentially large number of recipients.
- Add eight new BACnet engineering units.
- Add Annex J -BACnet/IP and supporting definitions.
Approved by ASHRAE and the American National Standards Institute on March 31, 2023.
- Add new and correct existing tests for the Network Layer, p. 3
- Add new and correct existing tests for the MS/TP Data Link Layer, p. 15
- 135.1-2019s-3 Add tests for the BACnet Secure Connect Data Link Layer, p. 17
- 135.1-2019s-4 Add tests for IPv6, p. 68
- 135.1-2019s-5 Add new and correct existing BACnet/IP Functionality Tests, p. 84
- 135.1-2019s-6 Renumber Clause 15, p. 107
- 135.1-2019s-7 Add new and correct existing Object Support Tests, p. 108
- 135.1-2019s-8 Add new and correct existing Application Service Initiation Tests, p. 335
- 135.1-2019s-9 Add new and correct existing Application Service Execution Tests, p. 419
- 135.1-2019s-10 Improve existing DEFINITIONS, p. 562
- 135.1-2019s-11 Improve the EPICS FILE FORMAT and the EPICS CONSISTENCY TESTS, p. 563
- 135.1-2019s-12 Add new and improve existing CONVENTIONS FOR SPECIFYING BACnet CONFORMANCE TESTS, p. 565
- 135.1-2019s-13 Add new and improve existing SPECIAL FUNCTIONALITY TESTS, p. 568
- 135.1-2019s-14 Apply miscellaneous editorial changes, p. 587
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
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
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
This addendum is final and was approved by ASHRAE on May 31, 2018 and by the American National StandardsInstitute on June 1, 2018.
- Add Property_List property tests.
- Add tests for DUPLICATE_ENTRY error code.
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
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
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 Off normal 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
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
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
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
This addendum is final and was approved by the ASHRAE Standards Committee on January 29, 2011; by the ASHRAE Boardof Directors on February 2, 2011; and by the American National Standards Institute on February 3, 2011.
- Revise BACnet/IP tests
This addendum is final and was approvedby 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
This addendum is final and was approved by the ASHRAE Standards Committee on January 29, 2011; bythe 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 Test
- Add Device Restart Notification Tests
- Add Schedule Written Datatypes Tests
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
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
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 "off normal" tests.
- Label conditionally-writable properties in the EPICS
- Add new object types
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.
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