BIM has become a fundamental part of modern architecture, engineering and construction. But not every BIM workflow works at the same level of maturity.

This is where BIM Levels 0, 1, 2 and 3 come in. They help explain how BIM workflows have developed, from basic CAD-based processes to more structured and collaborative ways of working.

The BIM levels are closely linked to the UK’s approach to BIM and have become widely used when discussing BIM maturity across the AEC industry. While the terminology has evolved over time, understanding these levels is still useful for anyone learning BIM or working on projects that involve different teams, models and information systems.

Whether you are an architecture student in the UK, a Revit professional in India, or an AEC professional working on international projects, understanding these concepts can help you make sense of modern BIM workflows and the skills employers expect.

At ASDAV, we help students and professionals build practical BIM and Revit skills for real-world AEC work. Our Revit course for London and UK students and international learners cover Revit modelling, BIM workflows, documentation, coordination and project-based learning.

In this guide, we will explain BIM Levels 0, 1, 2 and 3, what each level means, how they differ, and how they relate to modern BIM standards and professional practice.

What Are BIM Levels?

Construction projects generate huge amounts of drawings, models and project information. Architects, engineers, contractors and other teams need to create, update, share and manage this information throughout a project. As construction technology has developed, the way this information is created, managed and shared has also changed significantly.

BIM maturity levels provide a simple way to describe this progression. They show how a project or organisation can move from basic CAD-based workflows to more structured, collaborative and integrated approaches to managing digital information.

The traditional BIM maturity model is commonly described through four levels:

Level 0 → CAD-based work: Mainly 2D drawings with limited collaboration and information management.
Level 1 → Managed 2D/3D information: A combination of 2D and 3D CAD with more structured processes and information sharing.
Level 2 → Collaborative BIM and federated models: Different teams create and manage their own information-rich models that can be brought together for coordination and collaboration.
Level 3 → Highly integrated digital built environment: A vision for greater integration, interoperability and information sharing across the project and asset lifecycle.

These levels came from the Bew-Richards BIM maturity model and became particularly associated with the UK’s BIM journey. The UK played an important role in developing and promoting a structured approach to BIM, with BIM Level 2 becoming a major reference point for collaborative BIM delivery.

It is important to understand that these levels describe BIM maturity, not simply the software being used. Using Revit, for example, does not automatically mean a project is operating at BIM Level 2. The level also depends on how teams create, manage, exchange and coordinate information.

The industry has continued to evolve since the original maturity model was introduced. Today, frameworks such as ISO 19650 place greater focus on information management and collaboration across the asset lifecycle.

However, understanding Levels 0 to 3 remains useful for understanding how BIM has developed and why modern BIM workflows work the way they do.

What Do BIM Levels Actually Measure?

BIM levels are not simply about whether a project uses 2D drawings or 3D software. They describe how effectively a team creates, manages, shares and coordinates project information.

As BIM maturity increases, technology, information management, collaboration, standards and project workflows generally become more structured.

BIM Level 0: Unmanaged CAD

BIM Level 0 represents the most basic stage in the traditional BIM maturity model. It is mainly based on 2D CAD drawings, with project information created and managed in separate files and limited collaboration between project teams.

At this stage, CAD has replaced manual drafting, but the overall workflow remains largely unchanged. Architects, structural engineers and MEP teams typically work on their own drawings, with information shared manually between them.

Key characteristics of BIM Level 0

Primarily 2D CAD drawings
Separate files and workflows
Limited collaboration
Manual information exchange
Limited information management
Minimal model coordination
Higher risk of inconsistent drawings
Heavy reliance on manual updates

Example of a BIM Level 0 Workflow

An architect creates a commercial building’s plans and elevations in AutoCAD. The structural and MEP teams work on separate drawings based on the architect’s files.

If the architect later moves a wall, the change has to be shared with the other teams, who must manually update their drawings. If someone misses the update, different teams may end up working with different versions of the project.

This is the main limitation of Level 0. Project information remains fragmented across separate drawings and teams rather than being managed through a connected BIM workflow.

BIM Level 1: Managed 2D and 3D Information

BIM Level 1 represents a step forward from basic CAD workflows. Teams start using a combination of 2D drawings and 3D models, while project information becomes more structured and better managed. However, different disciplines may still work largely within their own separate workflows.

The focus at this level is not just on creating drawings, but on introducing more consistent processes for creating, storing and sharing project information.

Key characteristics of BIM Level 1

Combination of 2D and 3D CAD
Structured project information
Standardised drawing processes
Defined naming and file structures
Common Data Environment (CDE)
Improved information sharing
Better document management
Limited multidisciplinary collaboration
Separate discipline models

Example of a BIM Level 1 Workflow

An architect creates the building design using a 3D modelling tool such as Revit while still producing 2D drawings for documentation. Project files are stored and shared through a more organised system or Common Data Environment.

The structural and MEP teams may also use 3D tools, but each discipline generally manages its own model. Information is shared more systematically than at Level 0, but the models are not yet fully integrated into a collaborative BIM workflow.

The key difference is that Level 1 introduces structured digital information management, but teams still largely work in separate silos.

BIM Level 2: Collaborative BIM

BIM Level 2 represents a major shift from working with separate digital files to working collaboratively with structured, information-rich models. Different project teams can create their own discipline-specific models while sharing information through agreed processes and a Common Data Environment (CDE).

The models do not necessarily have to be combined into one single file. Instead, they can be brought together as a federated model for coordination, design review and clash detection.

Key characteristics of BIM Level 2

Information-rich 3D BIM models
Multidisciplinary collaboration
Federated models
Common Data Environment (CDE)
Defined information exchange processes
Model coordination
Clash detection
Standardised BIM workflows
Greater information consistency
Better project-wide visibility

Example of a BIM Level 2 Workflow

For a commercial building, the architect creates an architectural Revit model, while the structural and MEP teams create their own models. These models are shared through a CDE and brought together for coordination.

The teams can review the combined model in tools such as Navisworks to identify issues, such as an MEP duct passing through a structural beam, before construction begins.

The key difference is that teams remain responsible for their own models but actively coordinate and exchange information through a structured collaborative workflow.

BIM Level 3: Integrated Digital Built Environment

BIM Level 3 represents the highest stage in the traditional BIM maturity model. It was envisioned as a more integrated digital environment where project information could be shared and connected across different disciplines and throughout the asset lifecycle.

Unlike Level 2, which typically involves separate discipline models that are federated for coordination, Level 3 envisioned much deeper integration, interoperability and information sharing between project participants.

Key characteristics of BIM Level 3

Highly integrated digital workflows
Greater interoperability between systems
Shared project information
Open data and information exchange
Greater lifecycle information management
Integration between design, construction and operation
Advanced collaboration
Connected digital built environment
Potential integration with smart technologies

Example of a BIM Level 3 Workflow

A major infrastructure project uses connected digital information throughout its lifecycle. Design information is developed collaboratively, construction teams use the same structured information, and relevant asset data is carried forward into operation and maintenance.

Information can move between different systems and project stages with less duplication, helping owners and facility teams make better decisions after construction is complete.

However, it is important to note that BIM Level 3 is largely a vision from the traditional BIM maturity model rather than a current universal standard.

Modern BIM practice has moved toward frameworks such as ISO 19650, which focus on structured information management and collaboration rather than simply assigning a project a BIM Level.

BIM Levels 0 vs 1 vs 2 vs 3: Quick Comparison

The four traditional BIM levels show how project workflows progress from basic CAD-based drafting to increasingly structured, collaborative and integrated digital environments.

Feature	BIM Level 0	BIM Level 1	BIM Level 2	BIM Level 3
Main approach	2D CAD	Managed 2D and 3D information	Collaborative BIM	Integrated digital environment
Primary focus	Drawing production	Structured information	Collaboration and coordination	Integration and interoperability
Modelling	Mainly 2D	2D and 3D	Information-rich 3D models	Highly integrated digital models
Collaboration	Very limited	Limited	Multidisciplinary	Highly integrated
Information sharing	Manual	Structured sharing	Managed information exchange	Connected information environment
CDE	Not typically used	Introduced	Central to the workflow	Highly integrated
Model coordination	Minimal	Limited	Strong	Highly integrated
Model approach	Separate drawings	Separate discipline files/models	Federated discipline models	Historically envisioned shared/integrated environment
Standards and processes	Limited	More defined	Standardised BIM processes	Highly integrated processes
Lifecycle focus	Design documentation	Design and documentation	Design and construction coordination	Whole asset lifecycle
Modern context	Historical maturity stage	Historical maturity stage	Still commonly referenced	Primarily a historical/aspirational concept

Note: BIM Levels 0 to 3 describe the traditional BIM maturity model. They should not be confused with BIM dimensions such as 3D, 4D or 5D. Modern BIM practice increasingly focuses on structured information management through frameworks such as ISO 19650.

BIM Levels vs ISO 19650: What Has Changed?

The traditional BIM Levels 0 to 3 model helped explain how BIM maturity developed, particularly through the UK’s BIM journey. However, BIM practices have evolved, and the industry now places greater emphasis on information management, collaboration and consistent processes.

From BIM Levels to Information Management

The key shift is that ISO 19650 does not classify projects simply as Level 1, Level 2 or Level 3. Instead, it provides a framework for managing information throughout the lifecycle of a built asset.

ISO 19650 focuses on:

Clear information requirements
Defined roles and responsibilities
Common Data Environments (CDEs)
Structured information exchange
Consistent naming and documentation
Collaborative workflows
Information management across the asset lifecycle

What This Means Today

BIM Levels are still useful for understanding the history and maturity of BIM workflows, especially when working with older UK BIM terminology.

However, for modern BIM projects, professionals are increasingly expected to understand ISO 19650 principles and structured information management, rather than simply identifying a project as BIM Level 2 or Level 3.

In simple terms, BIM Levels explain how BIM maturity developed, while ISO 19650 provides a more modern approach to how project information should be managed and exchanged.

Understanding BIM Levels and Building Practical Revit Skills

Understanding BIM Levels helps architects, engineers and designers see how BIM workflows have developed, from basic CAD-based drawings to more structured and collaborative digital processes. It also helps professionals understand why information management, coordination and collaboration are now such important parts of modern AEC projects.

For architects and designers, learning BIM concepts is only one part of becoming job-ready. Practical knowledge of tools such as Revit is equally important. Revit is widely used for architectural modelling, documentation, design coordination and creating information-rich building models.

At ASDAV, our Revit courses are designed to help students and professionals build practical Revit skills through structured learning and real-world workflows. Our Revit Certification Course in London, UK covers essential Revit concepts, modelling, documentation and project-based skills to help learners build a stronger foundation for professional AEC work.

If you are an architecture student, designer or AEC professional looking to learn Revit and improve your BIM skills, explore our Revit Certification Course in London, UK and take the next step in your BIM learning journey.