Overview of All Objects

Outliner Panel

The Outliner panel (top right) shows a hierarchy of all currently loaded physical Objects in your IFC project. These Objects correlate to what you see in the Viewport panel.

Object Naming and Hierarchy

• Every Object in the Outliner represents an IFC Element.
• Objects are named as Class/Name (e.g., IfcBuilding, IfcWall).
• The class prefix represents the type, and the name is the object name.
• The hierarchy breaks down from large spaces (site, building) to smaller spaces (storeys, rooms). The root is always an IfcProject object.
• Click the triangle to toggle hierarchy.

Tip: In large projects, use Shift-LMB on the triangle to recursively toggle the hierarchy. Drag MMB to pan left/right.

• Use the filter box to quickly find objects by name or type.

Selecting and Isolating Objects

• Clicking an object in the Outliner also selects it in the Viewport.
• Use View > Frame Selected to zoom to the object in the Viewport.
• Isolate portions of your project by toggling the Tick Icon next to collections.
• To isolate a single building storey: disable the Tick Icon next to IfcProject (hides all), then enable it for an IfcBuildingStory.

Viewing Element Classes

What is an IFC Class?

• The Class is an international classification (e.g., Wall, Slab, Door). Every IFC element must have a Class.
• Classes determine what types of properties and relationships an element can have. For example, a Wall Class can have a fire rating property, but a Grid Class cannot.

Note: There are hundreds of Classes (including non-geometric ones like Task, Occupant, CostItem). This guide focuses on simple physical Classes. You do not need to memorize all available Classes.

How to View an Object's Class

1. Click on an object in the Viewport or Outliner panel.
2. Switch to the Object Properties tab in the Properties panel.
3. The Class name appears in the IFC Class subpanel.

• The Class of our roof is IfcSlab (also used as a prefix in the Outliner). The selected object's name is shown in the top left of the Viewport.

Warning: Sometimes, an IFC model will use the wrong Class (e.g., a chair as Wall Class instead of Furniture Class). IfcBuildingElementProxy is used for elements without a more semantic Class. Many proxies indicate a low quality IFC model.

• After IfcSlab you may see ROOF. This is the Predefined Type (e.g., roof slab vs. other slabs). The Predefined Type is optional.

Selecting and Isolating by Class

• Press the Select Icon to select all objects of the same Class.
• Isolate: Object > Show/Hide > Hide Unselected (Shift-H).
• Show all: Object > Show/Hide > Show Hidden Objects (Alt-H).
• Hide selected: Object > Show/Hide > Hide Selected (H).

Note: Blender’s hotkeys are context sensitive. Make sure your mouse is over the Viewport panel when you press a hotkey.

• Enable Scene Statistics (right-click status bar) to see counts like Objects 4/4 (4 selected out of 4). Useful for counting objects like toilets.