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How to deal with IfcClassification using Revit 2020

Entity inheritance

https://standards.buildingsmart.org/IFC/RELEASE/IFC4/ADD2_TC1/HTML/link/ifcclassification.htm

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:

  1. Assign classification via assembly code
  2. Assign classification via ClassificationCode parameter
  3. Assign classification via Omniclass Number
  4. 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

Figure 1 Prepare the settings for Assembly Code use

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

Figure 2 Edit Type – Assembly Code parameter value
Figure 3 After selection the Assembly Code – Assembly Description will be filled automatically
Figure 4 Be aware that during IFC export settings, the Classification Settings are using the Classification field name Assembly Code

Option 2: Assign classification via Classification Code

  1. Select tab Manage
  2. Select Project Parameters
  3. Add Project Parameter
  4. Use Name ClassificationCode
  5. Recommend to use Shared parameter
  6. Place under Parameter group IFC Parameters
  7. 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!

Figure 5 adding the Shared Paramter ClassificationCode into project and select the Categories

Then fill this Revit parameter ClassificationCode with the convention:
[NAME OF CLASSIFICATION] CODE:DESCRIPTION

Figure 6 Assigning the classification code to objects
Figure 7 Be aware that during IFC export settings, the Classification Settings are using the Classification field name ClassificationCode
Figure 8 Result shown in Solibri Office

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.

Figure 9 Edit Family to access Omniclass Number parameter on Family level
Figure 10 Select the OmniClass Number paramter and click on the … The OmniClass Table pop-up – Select the classification code – automatic the OmniClass Title will be filled.
Figure 11 Be aware that during IFC export settings, the Classification Settings are using the Classification field name OmniClass Number
Figure 12 Result shown in Solibri Office

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

The add-in is after installation available in Add-Ins or BIM interoperability Tools

Some help – instructions are available on YouTube:

https://www.youtube.com/playlist?list=PL0RZIBv0pCfvgTJ3W9k5_6uRynKQsX-um

User Manual and instructions are available:

https://knowledge.autodesk.com/community/collection/standardized-data-tool-for-revit

Updated on July 29, 2022

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