Classification Systems
Classifying elements is one of the most critical steps in creating a usable and intelligent information model. Classification assigns meaning to elements: what they are, how they function, and how they should be handled in downstream processes such as costing, planning, facility management, and IFC export.
A consistent and properly applied classification system forms the foundation for automation, data validation, and model coordination.
Why Classification Matters
- ✅ Identifies what an element is, regardless of naming or geometry
- ✅ Supports data exchange (e.g., IFC, COBie)
- ✅ Enables rule-based checks and automation
- ✅ Allows for filtering, scheduling, and grouping
- ✅ Reduces ambiguity across disciplines and stakeholders
Built-In Option: Assembly Code
Revit includes a built-in Assembly Code parameter that is widely used for classification.
- It’s a Type parameter, which works well for Architecture and Structure.
- In MEP models, it can be less flexible since multiple instances of the same type may need different classifications (e.g., same pipe type used for multiple systems).
- DAQS supports reading the Assembly Code parameter where applicable.
⚠️ For MEP models, using Instance-level classification is often more appropriate.
DAQS-Specific Classification Handling
DAQS includes built-in support to handle classification schemes flexibly. Specifically:
- DAQS can be configured to recognize classification codes based on a main group prefix (e.g.,
4-
for piping,5-
for ventilation). - It can then verify whether the correct instance parameter is used to store classification codes based on element category or system type.
- This allows classification to work even when Assembly Code is insufficient.
Supported Classification Systems
DAQS currently supports multiple systems, including:
✅ Uniclass 2015
Uniclass 2015 is a unified classification system for all sectors of the UK construction industry. It is:
- Structured into tables (e.g., Ss for systems, Pr for products)
- Fully supported in DAQS
- Compatible with IFC and ISO 12006-based exports
📘 Read more: Uniclass 2015 Overview
Best Practices for Classification
- Use shared instance parameters for classification when flexibility is needed (e.g.,
ClassificationCode
). - Apply the classification early in the modeling phase to enable validation throughout the project.
- Ensure consistency by using predefined lists or lookups from your classification system.
- Don’t rely on type-based classification in MEP models unless all instances truly serve the same role.
How to Fix Classification Issues
- Identify the correct classification system for your project (e.g., Uniclass, NL/SfB, Omniclass).
- Apply classification codes using the correct parameter:
- Use
Assembly Code
where appropriate - Use custom/shared parameters for more flexible workflows
- Validate the format and code groupings using DAQS rules.
- Consult your BIM coordinator if you're unsure which table or structure to use.
🛠 If your project uses a custom classification scheme, DAQS can be configured to recognize and validate it. Contact us to set it up.