For BIM's Sake

No, this is not a new expression in the construction industry, at least not yet. BIM (building information modeling) has been talked about quite a bit lately, and we will talk about it a lot more in the years to come. The BIM discussion will go away when BIM becomes part of our daily toolset. In this editorial, I urge you to consider the use of BIM in your daily practice not for BIM’s sake, but for the project’s, the architecture profession’s, and your sake.

Figure 1. Snapshots of the 4D model for the Walt Disney Concert Hall (CIFE Working Paper #64) Click on individual graphic to view larger image.

All of us use two-dimensional (2D) and three-dimensional (3D) computer-aided design (CAD) for our work all the time, and 3D models have allowed many architects to design buildings that would have been difficult to build otherwise, as shown, in the snapshots from the four-dimensional (4D) model used to plan the construction of Walt Disney Concert Hall. But it is still astonishing to me and to all the students I teach that we, as a profession and industry, do not take advantage of building and experiencing our projects, or at least their difficult parts, in the computer first.

When a design team uses virtual building methods, amazing accomplishments can happen. For example, buildings can give the owner and users far better lifecycle performance when the mechanical engineer and the team share a 3D building information model to support each others’ analyses in a consistent and quick way. For a research lab the owner had specified a heating energy consumption target around 20 to 25 kWh/m3.

Figure 2. Use of BIM for energy calculations across design versions (courtesy Granlund, Helsinki)

The design team was able to meet this target and show throughout the design development that each design version still met the owner’s heating energy performance goals while also considering other building performance aspects using information from the same.

Figure 3. Use of BIM for other performance analyses (courtesy Granlund, Helsinki).

Contrast this building with a similar research facility where the owner did not use an integrated team supported by building information modeling methods. This facility ended up consuming 100 kWh/m3 of heating energy. After lots of tweaking, the owner reduced it to 50 kWh/m3. This is just one example of a high-performance building that was designed by an integrated design team supported with shared building information models.

All of us know what happens when we don’t coordinate the designs of the various disciplines in 3D, when we don’t sequence the project in 4D in the computer, when different disciplines repeatedly re-enter project information into their software tools, or even base their analyses on different versions of the design. We waste design effort, we miss opportunities to explore more design options more deeply inexpensively, we waste construction materials and time, we cannot easily understand the evolution of a design and its corresponding cost.

But maybe most important, we make the building industry unattractive for young, intelligent, and creative adults. One of my students recently built a small 3D model for a critical part of a health care project at the 80 percent design stage. She spent 60 hours converting the 2D drawings to a 3D model and had to stop the modeling effort because the coordination problems in 2D became so numerous that she simply could not proceed productively until the design team started to resolve the coordination problems. The professionals thought it was a good experience for the student to see such practical problems. The student, on the other hand, thought the whole method of designing the building—how the resources are allocated, where the time is spent, what deliverables are expected—simply did not make any sense because her experience on the project suggested there are good, easy-to-learn 3D tools to make designers more effective and efficient. In my experience, BIM has enabled for better learning experiences for my students, not only about the technology but about the process and content of design and construction.

With industry support, Stanford University’s Center for Integrated Facility Engineering (CIFE) has made it easier and more powerful to build projects in the computer first since its inception in 1988. As outlined above, we have found many benefits of BIM, but the use of BIM is messier than the theoretical ideal often shown (left part of Fig. 4). On a project where CIFE was invited to document the BIM-based design process, the architect, structural engineer, mechanical engineer, and contractor used the handoffs of BIMs shown on the right of Fig. 4. There are clearly challenges ahead to establish a better theoretical and practical foundation for BIM. I urge you to capitalize on the benefits of today’s 3D and 4D model tools now, however. More intelligent BIM, better BIM processes, and better buildings will follow.

Figure 4. Theoretical and actual BIM use (CIFE Technical Report #143) Click on individual graphic to view larger image.