What Is BIM and Why Is It Important?

BIM, or building information modeling, is an essential workflow process in the architecture, engineering, and construction (AEC) industry. By capitalizing on 3D models and shared data environments, BIM workflows enable a holistic approach to designing, constructing, and managing buildings.

Many AEC professionals think of BIM as the natural successor to computer-aided design (CAD). CAD was the first step towards the digitization of building projects —nowadays, BIM takes that digitization many steps further.

BIM allows designers to use data and 3D modeling to tell a better story of the building. This leads to transparent and more effective collaboration, reductions in project costs and timelines, improvements to design quality and building safety, and optimized facility management.

In this first chapter of the Beginner’s Guide to BIM, you’ll read more about what BIM is and why it’s important in today’s practice. You’ll also read about the history of BIM: how it has evolved and how it’s expected to continue evolving.

• What Is BIM?
• Why Is BIM Important?
• The History of BIM
• What Is BIM Software?

BIM stands for building information modeling, which is a process involving the creation and administration of digital models that represent the form and function of buildings.

BIM is often used as a way for cross-discipline project teams to collaborate in a way that’s efficient and transparent. A shared 3D model appended with information such as material costs, measurements, product specifications, and code compliance allows all project stakeholders to operate from the same information nearly in real time, which is a great benefit to projects.

It sounds like a no-brainer. But even today, BIM can be a stressor for practitioners who have yet to implement it. More and more municipalities and project owners are requiring it, and more and more project teams are using the framework for collaboration.

There’s good reason to feel excited and even confident about learning BIM, though. There are now decades of precedent of practitioners successfully implementing the workflows and reaping their rewards as well.

BIM allows all stakeholders to have access to a “universal source of truth” for the project throughout its lifecycle, an advantage that can be leveraged to make more informed decisions, ultimately reducing project costs and timelines.

This advantage extends to every phase of the project — design, construction, building management, and demolition. Having this central source of information about the built (or to-be-built) asset provides the opportunity to make decisions in a digital environment before implementing them physically.

This scenario resonates with many AEC professionals and serves as an example of why BIM continues to grow in popularity:

• The project architect, using a non-BIM 2D software, revises a drawing due to the client’s request.
• The architect sends the revised 2D plans to the structural engineer.
• The structural engineer manually checks the revised architectural drawings and finds interferences with the work they already did.
• The structural engineer revises and updates drawings to reflect changes.

If this scenario occurred when the architect and engineer were collaborating via BIM, it might look more like this:

• The architect revises the shared 3D model due to the client’s request.
• The structural engineer is notified of updates and interferences.
• The structural engineer finds that the revision interferes with the work they already did but can correct those pieces of the model without needing to restart.

It’s a basic example, but one that illustrates one major aspect of BIM collaboration: less time spent on revisions for all parties involved.

A defined avenue for collaboration and coordination allows each project participant to use their preferred software, if that software can facilitate a BIM process.

There are a variety of BIM applications on the market that serve different parts of the BIM process. Solibri Model Checker is suited for model coordination and clash detection, while Vectorworks is suited for the architect to design the project. There are applications for issue tracking, clash detection, cost estimation, product specifications, project management, project scheduling, asset management, and so on. There are applications built for all aspects of BIM, so it depends on what your responsibilities are as you evaluate which is right for you.

Many BIM programs support the open-standard file formats IFC (Industry Foundation Classes) and BCF (BIM Collaboration Format), which is essential for effective collaboration. These non-proprietary file formats, whether directly integrated into the software or in need of an export, are the primary avenues through which AEC professionals can use practically whatever software they want yet still be able to work smoothly with others.

The first two decades of the 21st century have seen a digital transformation in the AEC industry. The use of BIM has increased rapidly as the industry has begun to realize the potential of digital technologies to improve the design, construction, operation, and demolition of buildings.

The evolution of the AEC industry into BIM workflows mirrors the transition from primarily producing hand-drawn documents into using CAD to produce those drawings. Now, the shift is from CAD into BIM.

The origins of BIM go as far back as the late 1970s. Chuck Eastman introduced a product called Building Description System, which was essentially the infancy of BIM as we know it today. Into the ‘80s, the Building Description System along with other products like GLIDE, RUCAPS, Sonata, Reflex, and Gable 4D Series were prohibitively expensive, which prevented a much larger adoption in the AEC industry. It wasn’t until the early 2000s when the term “BIM” became popularized, and companies like Vectorworks started producing more accessible authoring tools. 

According to the 2021 NBS Digital Construction Report, 71% of surveyed firms have adopted BIM, 25% said they will adopt it within five years, and 5% said they never will.

The 2022 AIA Firm Survey indicates that the use of BIM by small firms under 10 employees has seen a sharp increase of 15% between 2019 and 2021.

 It should come as no surprise that the coronavirus pandemic impacted the history of BIM. NBS’ report states that, for 69% of those surveyed, the pandemic accelerated their adoption of digital technologies and ways of working; 25% said it had no effect, while 6% said the pandemic slowed their adoption of digital technologies.

BIM software can help manage one or several major aspects of a BIM workflow, such as design or coordination.

Design-oriented BIM software used by architects contains 3D modeling capabilities that allow designers to create digital representations of the built asset. This kind of software can append data to geometry and automate aspects of the documentation process.

Coordination programs such as Solibri Model Checker and Revizto tend to use the IFC and BCF file formats to combine each stakeholder’s model into one master model and to communicate issues. These programs have functionality to perform clash detection analysis and to assign issues for users to fix.