An IfcClassification is used for the arrangement of objects into a class or category according to a common purpose or their possession of common characteristics. A classification in the sense of IfcClassification is taxonomy, or taxonomic scheme, arranged in a hierarchical structure. A category of objects relates to other categories in a generalization-specialization relationship. Therefore the classification items in an classification are organized in a tree structure.
The IfcClassification identifies the classification system or source to which a classification reference refers to. Each classification reference may reference an instance of IfcClassification. A classification system declared may be either formally published, or it may be a locally defined method of classifiying information.
NOTE Examples for such formally published classifications are Omniclass, Uniclass, Masterformat, or DIN277.
There are several options for creating classifications in Revit. Most used for assigning classification code to elements are:
- Assign classification via assembly code
- Assign classification via ClassificationCode parameter
- Assign classification via Omniclass Number
- Using softwaretools, for example Classification manager for Revit https://interoperability.autodesk.com/classificationmanager.php
Option 1: Assign classification via assembly code
1) Select tab Manage
2) Additional Settings
3) Choose Assembly code
4) Browse for a classification file for example OmniClassTaxonomy.txt file
Normally stored with installation Revit for example version 2020
C:\Users\xxxx\AppData\Roaming\Autodesk\Revit\Autodesk Revit 2020
Or download via: https://download.autodesk.com/us/revit/OmniClassTaxonomy.txt
1) Select Edit Type
2) Select Assembly Code – pick the corresponding classification code (in this example OmniClass code)
3) Automatic the corresponding Description will be filled in – Assembly Description
Option 2: Assign classification via Classification Code
- Select tab Manage
- Select Project Parameters
- Add Project Parameter
- Use Name ClassificationCode
- Recommend to use Shared parameter
- Place under Parameter group IFC Parameters
- Select the Revit categories where it is appropriate to use classification
Using more than one Classification is possible. Revit supports multiple classifications, (up to 10 supported) by using parameter:
ClassificationCode, ClassificationCode(2), ClassificationCode(3), …, ClassificationCode(10)
NOTE: Don’t use ClassificationCode(1) for the first Classification. Use ClassificationCode for the first Classification!
Then fill this Revit parameter ClassificationCode with the convention:
[NAME OF CLASSIFICATION] CODE:DESCRIPTION
Option 3: Assign classification via Omniclass Number
Revit distinguishes between loadable families and System families (such as walls).
Most loadable families have already built-in parameters for Omniclass classification. These Revit parameters are: OmniClass Number and OmniClass Title. Note: These parameters are on family/Type level (so not to influence per instance!)
1) Load a family (in this example a structural beam)
2) Select an object – and choose Edit Family
3) By properties, select OmniClass Number – the 3 dots
4) Choose the correct OmniClass Number and automatic the OmniClass Title will fill.
Option 4: Using softwaretools, for example Classification manager for Revit
A add-in for Revit – classificationmanager – is available: https://interoperability.autodesk.com/classificationmanager.php
After installation the functions are available within Revit programm
Some help – instructions are available on YouTube:
User Manual and instructions are available: