What is BIM? Building Information Modelling Explained

Construction projects have come a long way from relying solely on paper drawings and disconnected design information.

Today, Building Information Modelling (BIM) allows project teams to work from a shared digital model, improving accuracy, collaboration and decision-making throughout the project lifecycle.

If you’ve come across the term BIM but aren’t sure what it means in practice, this guide explains the basics, why it has become the industry standard and how accurate survey data underpins every successful BIM project.

What is BIM?

The key distinction from traditional CAD: Every element, a wall, a beam, a pipe, carries information about its material, dimensions, cost, maintenance requirements and more.

Unlike traditional CAD drawings, BIM models contain both geometry and data. Every element within the model, whether it’s a wall, beam or service run, can hold information about dimensions, materials, specifications and maintenance requirements.

BIM has evolved through a number of maturity levels.

Level 0 relied on paper drawings and basic CAD.

Level 1 introduced managed digital information.

Level 2, mandated on all centrally procured UK government projects since 2016, established collaborative working through shared project information and coordinated models.

Level 3 represents a fully integrated digital environment.

However, the quality of any BIM model depends entirely on the quality of the information used to create it. A successful BIM workflow begins with accurate survey data, providing a reliable digital representation of the existing site or building.

This is where specialist survey companies such as ourselves play a critical role, capturing the precise information that forms the foundation of accurate BIM models.

The Key Benefits of BIM for Construction Projects

BIM allows architects, engineers and MEP consultants to work from coordinated information. Potential clashes, such as services running through structural elements, can be identified and resolved before work begins on site.

Because model elements contain measurable data, quantities and cost estimates can be generated directly from the model, helping reduce uncertainty during design and tender stages.

A 3D model is easier for clients and stakeholders to understand than a set of technical drawings. This helps support decision-making and reduces misunderstandings throughout a project.

Resolving issues during the design stage is significantly more cost-effective than making changes during construction. BIM helps reduce rework, minimise waste and improve programme certainty.

The benefits of BIM continue after construction is complete. The model becomes a valuable record of the asset, supporting maintenance, refurbishment and compliance for the life of the asset.

For refurbishment and retrofit projects in particular, accurate existing building information is critical. Laser scanning and measured surveys create detailed point clouds that allow BIM models to be developed with confidence.

Autodesk Revit remains the most widely used BIM platform in the UK. Models produced in Revit can be shared across project teams, supporting a consistent and efficient design process.

Before commissioning a BIM model, it’s important to establish the required Level of Detail (LOD), as this will influence both the survey specification and final deliverables.

BIM Services at Kemp Engineering & Surveys

Kemp Engineering & Surveys provides BIM-ready survey data for projects across Devon, Cornwall and the wider South West.

Working alongside its wider surveying services, Kemp delivers accurate information collected by RICS-regulated professionals and converted into practical digital deliverables for design and construction teams.

3D Point Cloud Surveys

Using terrestrial laser scanners and UAV (drone) technology, we capture millions of highly accurate survey points across a building, structure or site.

The resulting point cloud creates a detailed digital representation of existing conditions, recording dimensions, levels and spatial relationships with exceptional precision.

Point cloud surveys are particularly valuable for refurbishment, retrofit and heritage projects where accurate existing information is essential before design work begins.

Revit & BIM-Ready Models

Kemp converts measured survey data and point cloud data into accurate Revit models that support BIM workflows across the wider project team.

Rather than creating design-stage BIM content, Kemp focuses on producing survey-grade, BIM-ready models that provide an accurate representation of existing buildings and infrastructure.

These models give architects, engineers and contractors a dependable starting point for design development, coordination and project planning, helping to reduce risk and improve decision-making from the outset.

Digital Twin Surveys

Digital twin technology combines accurate survey data with interactive digital environments, making building and asset information more accessible to project teams and stakeholders.

Kemp delivers digital twin solutions through platforms such as Matterport, allowing users to virtually navigate a site, take measurements and access location-specific information remotely.

Point clouds and Revit models can also be hosted and shared through Autodesk Viewer or Leica Truview, providing easy browser-based access to survey data without the need for specialist software.

Together, these tools create a connected digital record of an asset that supports project planning, collaboration, maintenance and long-term asset management.

Supporting Projects at Every Stage of Delivery

From initial surveys through to as-built records, Kemp supports clients throughout the project lifecycle. The company works with organisations ranging from local authorities and developers to major contractors, including Balfour Beatty, AECOM, Kier and Morgan Sindall.

BIM isn’t just for large-scale developments. Any project involving an existing building, complex site or detailed design process can benefit from accurate, data-rich models.

To find out what BIM could bring to your next project, speak to the Kemp team about a Revit model or point cloud survey.