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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

  1. Identify the correct classification system for your project (e.g., Uniclass, NL/SfB, Omniclass).
  2. Apply classification codes using the correct parameter:
  3. Use Assembly Code where appropriate
  4. Use custom/shared parameters for more flexible workflows
  5. Validate the format and code groupings using DAQS rules.
  6. 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.