BIM classification is the systematic organization and categorization of information within a Building Information Model (BIM) using standardized systems. It is fundamentally about defining "what things are" within a design, construction, or as-built model, ensuring that all elements speak a common, understandable language across different stakeholders and project phases. This structured approach helps AEC (Architecture, Engineering, and Construction) practitioners and large capital programs manage and exchange information efficiently throughout a project's lifecycle.
Why is BIM Classification Essential?
Effective BIM classification is crucial for enhancing project efficiency, data interoperability, and long-term asset management. It transforms raw model data into intelligent, actionable information.
- Standardized Communication: It provides a common language for all project participants, from architects and engineers to contractors and facility managers, streamlining communication and reducing misinterpretations. This is especially vital for large capital programs where consistency across multiple models is paramount.
- Improved Interoperability: By standardizing object definitions, classification systems facilitate seamless data exchange between different software applications and disciplines, overcoming common barriers in collaborative BIM workflows.
- Enhanced Information Retrieval: Classified data is easily searchable, allowing users to quickly locate, filter, and analyze specific components or information sets within complex models.
- Better Data Management: It supports robust information management throughout the project lifecycle, from design and procurement to construction, operation, and eventual demolition.
- Cost and Time Savings: Standardized classification aids in accurate quantity take-offs, cost estimation, scheduling, and risk management, leading to more predictable project outcomes.
- Asset Lifecycle Management: For owners and operators, classified BIM data forms a rich information backbone for facility management, maintenance scheduling, and asset tracking, optimizing the operational phase of a building.
How BIM Classification Works
BIM classification involves assigning specific codes, names, or identifiers to elements within a BIM model based on their function, form, material, location, or other attributes. These codes are part of a hierarchical structure defined by a chosen classification system.
- Selection of a System: Projects adopt a recognized classification system (e.g., Uniclass 2015, OmniClass).
- Element Tagging: Each object in the BIM model (e.g., a wall, door, beam, pipe) is tagged with a unique classification code from the selected system.
- Attribute Assignment: Beyond the basic classification, elements are also assigned specific attributes (e.g., fire rating for a door, material for a wall, flow rate for a pipe) that enrich their data.
- Information Structure: The classification system provides a logical structure that allows for organizing information at various levels of detail, from entire systems to individual components.
Prominent BIM Classification Systems
Several globally recognized BIM classification systems exist, each tailored to different regional needs or project focuses. Adopting a specific system is often driven by national standards, client requirements, or industry best practices.
Here are some widely used systems:
- Uniclass 2015 (UK): A comprehensive, harmonized classification system developed by NBS for the UK construction industry. It organizes information across a wide range of tables, covering entities, activities, elements, systems, products, and more. It is increasingly adopted internationally due to its flexibility.
- Example: A solid wall might be classified under Pr_20_20_85_90 in the Products table, specifying its type.
- OmniClass (North America): Developed by the Construction Specifications Institute (CSI) and Construction Specifications Canada (CSC), OmniClass is a broad system used primarily in North America. It encompasses 15 tables that classify every aspect of construction, from facilities and spaces to elements and materials.
- Example: A particular type of door assembly could be found within the 'Products' table.
- MasterFormat (North America): Also from CSI/CSC, MasterFormat is a well-established standard for organizing construction specifications, procurement requirements, and cost data. While not a comprehensive BIM classification, it is widely used for structuring information related to construction materials and methods.
- Uniformat (North America): A standard for classifying building elements by functional parts (e.g., substructure, shell, interiors, services). It is commonly used for early-stage cost estimating and life-cycle cost analysis.
- CoClass (Sweden): An object-oriented, harmonized classification system developed in Sweden, designed to support information management throughout the entire lifecycle of a facility. It focuses on classifying objects, activities, and characteristics.
Comparison of Key Systems
| Classification System | Primary Region / Focus | Key Features |
|---|---|---|
| Uniclass 2015 | UK, International / Comprehensive, harmonized | Multiple interrelated tables, flexible for various disciplines and project stages |
| OmniClass | North America / Broad construction information | 15 tables covering all aspects of construction, from high-level to detailed |
| MasterFormat | North America / Construction specifications & procurement | Standardized numbering system for organizing specifications and cost data |
| Uniformat | North America / Elemental cost analysis | Classifies by functional building elements, ideal for early costing |
| CoClass | Sweden / Object-oriented, lifecycle management | Focus on clear object definitions and attributes for lifecycle use |
Practical Applications and Solutions
Implementing BIM classification effectively involves several practical considerations:
- Early Adoption: Integrate classification principles from the initial stages of a project to ensure consistency and minimize rework.
- Common Data Environment (CDE): Utilize a CDE that supports and enforces the chosen classification system, ensuring all shared models and documents adhere to the standard.
- Model Authoring Guidelines: Develop clear guidelines for modelers on how to apply classification codes to various elements.
- Auditing and Validation: Regularly audit BIM models to ensure correct and consistent application of classification codes. Tools exist to automate this process.
- Stakeholder Training: Provide training to all project participants on the chosen classification system and its importance.
BIM classification is more than just tagging elements; it's a strategic approach to managing information that empowers smarter, more collaborative, and more efficient project delivery across the entire built environment lifecycle.
