Collision Detection

Detect intersections between building components from different trades.

Overview

Collision detection analyzes the geometry of loaded models and finds components that intersect with each other.

Typical use cases:

• MEP pipes running through structural elements
• Windows incorrectly positioned in walls
• Installations colliding with doors

Starting Collision Detection

1. Load at least one model (preferably: multiple trades)
2. Click on → "Collision Detection" in the toolbar
3. Select the categories to check
4. Click "Start Check"

Background Processing

Collision detection runs in the background:

• You can continue working with the viewer while the check runs
• Progress is displayed in the status bar
• Results appear automatically when available
• The check can be cancelled at any time

Large Models

For models with many elements, the check may take longer. Thanks to background processing, the application remains fully usable during this time.

Results

Results are displayed in a list:

Column	Meaning
Element A	First colliding element
Element B	Second colliding element
Type	Type of collision
Severity	Critical / Warning / Info

Selecting a Collision

Click on a row in the results list:

• The colliding elements are highlighted in the viewer
• The view automatically zooms to the collision
• Both elements are selected

Filters

Filter the results by:

• Category - Only specific IFC types
• Severity - Only critical collisions
• Status - Resolved / Unresolved

Marking Collisions

You can mark collisions as "resolved" or "to review":

1. Right-click on the collision
2. Select status:
   • Unresolved - Still to be addressed
   • Resolved - Has been corrected
   • Accepted - Intentional intersection

Note

Collision results are saved to the database and will persist when you reload the project. You can review previous collision checks at any time.

Settings

Tolerance

Set a minimum distance below which elements are considered colliding:

• 0 mm - Only actual intersections
• 10 mm - Also very close elements
• 50 mm - Also potential conflicts

Exclude Categories

Exclude specific IFC types from the check:

• IfcSpace - Spaces (often intentionally overlapping)
• IfcOpeningElement - Openings

Tips

Trade Checking

For the most effective checking, load models from different trades (Architecture + MEP + Structural) simultaneously.

Performance

For very large models, the check may take a few seconds. Progress is displayed.

See Also

• 3D Viewer - Navigation and element selection
• Advanced Filters - Filter elements by IFC type
• Model Comparison - Detect version changes
• Real-time Collaboration - Synchronize check results