Building Information Modelling — BIM — has transformed how construction projects are designed, coordinated, and managed in the UK over the past decade. This guide explains what BIM actually is in plain terms, what it can do for your project, and how to get started.

What is BIM?

BIM is a process centred on the creation and use of an intelligent digital model of a building or infrastructure asset. Unlike a conventional CAD drawing which is a two-dimensional representation of a design, a BIM model is a three-dimensional digital model that contains information about every element of the building — its geometry, its materials and specifications, its cost, its maintenance requirements, and its performance characteristics.

A door in a BIM model is not just a shape on a drawing — it has a manufacturer, a specification, a fire rating, a maintenance schedule, and a cost. This information can be used for design, procurement, construction management, and facilities management throughout the life of the asset.

What is the difference between BIM and CAD?

CAD produces drawings — two-dimensional representations of a design in digital format. BIM produces an information model — a three-dimensional digital representation containing both geometry and data about every building element.

A well-managed BIM project generates 2D CAD drawings automatically from the model, ensuring drawings are always consistent with the model data.

The benefits of BIM for UK construction projects

Clash detection — BIM software automatically identifies where building elements from different disciplines clash in 3D space, allowing resolution before construction begins. Improved coordination — all design team members work from the same model. Accurate cost information — BIM models generate accurate material quantities directly from the model. Better facilities management — information embedded in a BIM model can be handed over to the building operator at completion for the life of the asset.

BIM levels explained

BIM Level 0 is unmanaged CAD in 2D. Level 1 is managed CAD in 2D and 3D. Level 2 is a collaborative process using federated 3D models with data shared in a Common Data Environment — mandated by the UK government for public sector construction projects since 2016. Level 3 is a single integrated model shared by all parties in real time.

What software is used for BIM?

Autodesk Revit is the dominant BIM authoring tool in the UK. Navisworks is widely used for clash detection and model review. Other tools include ArchiCAD, Bentley AECOsim, and Trimble Tekla for structural steelwork.

How to get started with BIM outsourcing

Outsource CAD provides BIM and Revit outsourcing services for architects, engineers, and contractors across the UK. Contact us to discuss your requirements.

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