Managing Properties and Classifications in Archicad 28: A BIM Data Guide

Based on Graphisoft’s Archicad 28 Help documentation, this guide explains how to organize properties and classifications in a project. In Archicad, properties are searchable information added to elements or building materials, while classifications are systems for organizing project elements and related data. Used together, they let you define which information each element should carry. The documentation does not specify a publication date or any additional version requirements; this guide follows the interface and options described in Archicad 28 Help.

1. Plan your data model first

Before creating properties, decide which project elements need classifications and what information each class requires. For example, a product might include a model, serial number, or price; an element might include a fire resistance rating or thermal transmittance value. These examples are based on property types given in Archicad Help; choose the fields for your project according to your workflow and local standards.

Classification is more than a labeling tool. It helps organize elements and building materials, define relevant properties, support deliverables based on international classification standards, and structure data exchange using standards such as IFC. Archicad includes a default classification system; Graphisoft notes that different or additional systems can also be used to suit workflows and local standards.

2. Create properties in Property Manager

1. Go to Options > Property Manager. You can also open Property Manager from Classification Manager.

2. Use the property list to create a new property or group. You can do this from the list’s context menu, the New button at the bottom of the window, or the plus sign next to a group name.

3. In the New Property/Group window, select Property and enter a name. A property name must be unique within its group. Add the property to an appropriate group and click OK.

4. In the description field, enter formatting or unit information to help the person entering the data. For example, the Help documentation gives “minutes” for fire resistance and “W/m2K” for thermal transmittance. The description may appear in the element’s Classification and Properties panel when you hover over the property name.

5. Select the property and choose a data type in the right-hand section. The right type determines the format of the value you can enter; it also affects expression syntax for expression-based properties.

When Option Set is selected, you can add or remove options using Options Setup. The Allow multiple choices option lets users select more than one value for a property. These properties can be used in expressions when multiple choices are disabled; multi-select option sets and tag lists cannot be used as expression-based properties. Making this distinction at the outset helps preserve the data’s usability in later expression and reporting workflows.

3. Organize classifications and property access

Manage classification systems via Options > Classification Manager. To create a classification, select an item in the list; the new classification will be created under the selected item. Use the New button or context menu to choose the appropriate option: a new classification, a classification within a branch, or a new classification system. In the new classification window, you can enter an ID and name, and optionally add a description.

To set property access in Classification Manager, select one or more classifications from the list on the left. All makes all project properties available, while None makes no properties available. With Custom, click Edit to enable only selected properties. This lets you define a set of information relevant to a class, rather than making all project data available to every element.

Classifications and classification systems can be copied and edited. Classification sets can be imported and exported between projects as XML or Archicad files, either in full or in part. According to Graphisoft Help, the Import BIM Content or Download BIM Content commands can also bring classifications and their associated property and IFC mapping definitions into a project.

4. Use the data in schedules and data workflows

Making property values available in the project helps keep them visible and verifiable. Archicad can list and manage properties in Interactive Schedule, display them in labels, Zone Stamps, and door/window markers, and show elements according to properties using Graphic Overrides. This allows the same data to be used in different parts of model review and documentation.

Property data can be imported or exported between applications. The data structure can be exported to a spreadsheet, and property data can then be brought from the spreadsheet into Archicad elements or building materials. Classifications can also be used with Find & Select to find elements in a particular class, and as the basis for classification-based Graphic Override rules. Designing classifications and properties together therefore makes data useful not only in the model, but also in schedules, visual checks, and data exchange.

Common mistakes

• Failing to make a property name unique within its group or not deciding in advance which group it belongs in.

• Choosing an unsuitable data type for numerical, unit-based, or text data. In particular, remember that the data type affects syntax for expression-based properties.

• Assigning All or None to a classification without checking the required access level; if selective access is needed, consider Custom and Edit.

• Trying to use a tag list or multi-select option set in an expression-based property. The documentation does not support these uses.

In architecture, interior design, and visualization workflows, this setup helps describe model data more consistently. Establishing the data structure at the outset is useful, particularly on projects that need elements classified, properties managed in schedules, and data exported. However, the documentation does not explain hardware requirements or licensing terms, so no version-specific conclusions can be drawn on those topics. Teams should separately check that their classification system meets their deliverable and data exchange requirements.