How CAD and BIM Changed the Construction Industry

Over the past few decades, few technologies have influenced building design and construction as profoundly as Computer Aided Design (CAD) and Building Information Management (BIM).

First came CAD, which replaced manual drafting with digital design. Now, architects and engineers could create designs more quickly, to exact specifications. They could make modifications without starting over. They could check that components fit together.

This reduced the risk of human error, made it possible to explore unusual designs that would be extremely difficult to create by hand – and led to a wave of other trends and technologies, like 3D printing, that simply wouldn’t have been possible beforehand.

But while going digital was certainly a step up from hand-drawn designs, it didn’t do much to address workflows downstream.

Key information, models, drawings and schedules would still end up siloed. Different teams and stakeholders lacked ways to keep updated on progress or to share project knowledge with one another. Once work began on a project in the real world, CAD drawings faded into the background.

Until BIM came along.

From CAD to BIM

As the name suggests, BIM is about information and management, rather than design per se. The point of BIM isn’t to replace or upgrade CAD workflows, but rather to make these drawings part of a centralized ecosystem of project management. One that puts the building model at the core and updates in tandem with the project.

That said, the technology has had a significant impact on the way buildings are designed. For example:

Generative design

BIM opens up possibilities for AI-driven generative and parametric design. Using generative design tools, architects and engineers can set parameters, such as physical constraints, and automatically generate hundreds of potential solutions, inspiring innovative starting points for their work.

Typically, this takes place at the start of the project, but it can also be used to tackle problems that arise later on. Since BIM works with a “living” model, you can update your models and design iterations as you go, without having to start over.

Modular design

Combining CAD with BIM also facilitates a modular approach to construction, which informs the design process too. Architects and engineers can adopt sophisticated approaches to prefabrication, including 3D printing unique shapes and parts.

Since the construction process is no longer divorced from the design stage, you’re approaching the whole process holistically, testing out ideas and solving problems in the virtual space, first. Ultimately, this means architects can be bolder with their ideas – without increasing the risk.

Virtual reality

BIM is also used to make CAD models interactive, helping stakeholders to visualize the project. Using VR headsets, you can walk the site and “see” the future building as it will be laid out, getting a feel for how it will come together, figuring out where certain systems and features will need to be located, and even checking for potential safety hazards.

The benefits of BIM in construction

Here are 8 key ways that the BIM boom has shaped the modern construction site:

1. You have better information to work with

With BIM, all the key information about the project and the building is collated in one place. This information is far more comprehensive and valuable than that contained in traditional schematic drawings or CAD designs. It also develops over the course of the project, so it’s always relevant and accurate, no matter how much the building design changes along the way.

2. It keeps everyone in the loop

Not only will a BIM-based tool give you a complete overview of the project that’s totally up-to-date, it means all your stakeholders have a way to access this, too. You don’t need to worry so much about bringing everyone up to speed, or worrying that some of your colleagues could still be working from previous iterations of designs. (Provided that the BIM system that you use offers real-time updates, of course!)

3. It boosts productivity

From the architect to the GC to managers of individual crews, everyone along the chain can work faster with fewer hurdles. Workflows become streamlined, and it’s easier to identify and anticipate potential problems, reducing the risk of work stoppages and delays. Once you have a bird’s eye view of the project, with all the relevant data in one place, even managing your supply chains becomes an easier task.

4. Changes are simpler to accommodate

Alterations are much faster to make too. In the past, if the future owner wanted to request a relatively straightforward change to the design, like moving a wall back a few feet, the architect would need to painstakingly redraw the whole thing from scratch. Doing this with CAD might be a little faster than hand drawing it, but it boils down to the same time-consuming process. With BIM, the system is smart enough to know that moving a wall means moving a ceiling grid, for example, so your ceiling plan would automatically update, too. This cuts out a ton of steps from your workflow and makes it far easier to accommodate change requests on the fly.

5. It feeds into your other considerations

BIM goes much further than a simple building plan. It helps you collect and organize data that you need for other onsite considerations, too. That includes solar and energy analysis. Urban planning demands. Permissions, permits, project codes. Clash protection and conflict resolution. It’s a living document that matures along with the project. Long term, it may even be used as an operational digital twin by the building owners.

6. You avoid data loss

Over the course of a normal project, plenty of useful data leaks out, never to be put to good use. But with BIM, once the model is handed over to the contractor, it isn’t replaced, it’s refined. It’s continually developed and enriched. Information is added to the model constantly – and that information flows all along the project. Nothing is wasted.

7. It improves safety on the jobsite

With BIM, you combine all your models in one place and can view the status of the building as it is right now, at its current point of construction, as well as how it will look when it’s built. This helps you to track safety risks, points of egress, fall hazards and so on.

8. It keeps down costs

The more oversight you have, the more effectively and efficiently you can plan your schedules and manage your resources. You run a tighter ship, with fewer avoidable expenses, and you make it easier to stay on schedule and under budget throughout the project life cycle. Ultimately, that’s good news for your bottom line.

What’s next for BIM in construction?

Fundamentally, the exciting thing about BIM technology is that it produces more quality data than construction teams could ever have dreamed of having at their fingertips in the past. As this data is produced and captured, this opens up exponentially more opportunities that will shape the future of construction management.

We’re already seeing more technology on job sites, including drones, scanners, sensors and other devices used to map the area, assess safety risks, track progress and monitor other factors critical to the success of the project. In the future, this could even mean tracking construction workers’ vital signs, building sensors into PPE that detect health and safety risks, helping you to avoid incidents at work.

Imagine, for example, that schedulers and GCs had a simple, reliable way to factor in the effect of extreme weather like heat waves. A system that was precise enough to alert them as soon as their crews showed the earliest warning signs of heat exhaustion. How much safer and better managed could your job site be, thanks to this information? How much more accurate and realistic would your schedules become? And what about the impact this could have on your insurance premiums?

Data is an incredibly valuable, powerful resource. It opens up so many avenues for improvements and savings. Not only for the project you’re working on right now, but for all your future projects, too. BIM makes it easier to retain and share knowledge and insights gathered during the course of a project so that you can transfer this to the next one. It’s not just the technology that’s constantly learning and improving – your team is, too.

This is the key to understanding the future of CAD, BIM and related technologies: it’s not about a tool, it’s about a mindset. An attitude of continuous improvement, building on experience and wisdom, and seizing opportunities to refine your processes as and when they arise.

Haven’t started on your BIM journey yet? Find out more about using CAD and BIM together here >