Building Information Modeling (BIM)

Building information modeling (BIM) is a field within architecture, design, and construction that focuses on creating, altering, and managing digital representations of buildings and other structures. BIM involves the use of modeling software and is considered an evolution of computer-aided design (CAD) as well as a superior alternative to 2D CAD, which uses software to produce two-dimensional models of physical structures.

Unlike traditional CAD, BIM models are parametric, meaning that each element of the design can be linked to each other element so that any change made to the design or plan affects all parts of the overall design. BIM models typically have an informational layer that can be used to integrate data about pricing and sourcing, maintenance, deterioration, thermal conservation, and energy usage. Data associated with a BIM model can also be integrated in such a way that the information changes automatically if the model is altered.

Brief History

Building information modeling (BIM) is one of several computer-aided design models used by engineers, architects, and contractors working on construction and design projects. BIM is a form of computer design and is an evolution of the first digital design programs. The first computer-aided design (CAD) program was Sketchpad, developed in 1963 by Ivan Sutherland. The program used a light pen and a button interface to allow users to draw designs on a computer screen. When personal computers became a reality in the 1980s, the first practical digital design programs began to appear.

Charles Eastman was the first to propose creating a three-dimensional architecture system with linked data files. He first wrote about the concept in a 1974 paper and later received funding to begin working on the project. The Building Description System (BDS), a database that contained a library of building elements and was searchable by factors such as building material, cost, supplier, or subcontractor, was his first step.

Eastman went on to design the Graphical Language for Interactive Design (GLIDE) program in 1977, which contained many of the elements that became standard in later BIM programs. In 1982, the company Autodesk released its first version of AutoCAD software using two-dimensional design. The next major step in the development of BIM came from Budapest, Hungary, where physicist Gábor Bojár launched the ArchiCAD system in 1984. ArchiCAD used many of the same elements as Eastman’s BDS system and was considered a major technical leap forward, though the lack of widespread personal computer use limited the adoption of the program and many architecture firms continued to use traditional CAD programs.

The personal computer explosion of the 1990s led to the development of a host of new BIM programs. Advancements in the complexity of computer processing and data storage allowed new versions of BIM software to incorporate more detailed data management systems, making BIM more practical for commercial use. According to a 2013 SmartMarket Report from McGraw-Hill Construction, approximately 17 percent of companies in the United States were using BIM in 2007, and by 2012, this statistic increased to 71 percent.

Overview

While architects and engineers differentiate between BIM and CAD, both are models for creating and modifying three-dimensional data about physical structures. BIM software available by 2015 integrated drawing and visualization tools that are part of CAD programs but tended to include additional functionality that is not present in traditional CAD software.

One of the major advantages of BIM systems is the use of a parametric method for representing the relationship between objects. Traditional CAD systems tend to use explicit or coordinate-based models that treat each object as an individual, separate structure. By contrast, BIM systems are parametric, meaning that each element is modeled according to behaviors and attributes that are linked to every other element. If a designer changes the pitch, weight, thickness, or other qualities assigned to a roof, for instance, the other elements of the design automatically change as a result.

BIM systems also typically include data files associated with each component. In a BIM model, a wall will have an associated list that can show the materials needed for the project, the time needed to complete the component, the sourcing of materials, and a variety of other parameters. If a wall is supposed to have a door, the list connected to the wall will contain what designers call a "door schedule" that plans when the door is supposed to be installed within the wall. The data lists in BIM models are similarly linked to every related component in the model so that the lists automatically update whenever changes are made to any related element in the design.

While BIM systems are often described as three-dimensional, some architects and designers see BIM as "n-dimensional," meaning that additional dimensions can be modeled within the program. In addition to the three physical dimensions, BIM models can also integrate and model other aspects of the project that include the time needed for completion of individual components as well as the entire project, cost and maintenance of the project, and even estimates of how use will affect the structure.

By 2015, architects and engineers often used BIM for projects with specific needs or goals. When constructing a concert venue, engineers, designers, and contractors can use BIM programs to model the acoustic properties of components, materials, and rooms within a structure. Similarly, BIM modeling can help estimate factors including thermal and electrical conservation, energy use, and the environmental impact of materials. All of this information and any changes can be shared with the entire team working on the project, keeping the planning and building process smooth and updated.

Despite significant advantages, the widespread adoption of BIM systems only began in the 2010s, due partly to the complexity of earlier BIM software and conservatism in the building industry that inspired loyalty to the AutoCAD methodology. One of the modern trends in BIM design is for contractors and designers to use BIM models to involve the consumer in the design process. Using a BIM model, a contractor can demonstrate alterations or options to a customer.

Bibliography

Deutsch, Randy. BIM and Integrated Design: Strategies for Architectural Practice. Hoboken: Wiley, 2011. Print.

Eastman, Charles, et al. BIM Handbook: A Guide to Building Information Modeling for Owners, Managers, Designers, Engineers, and Contractors. 2nd ed. Hoboken: Wiley, 2011. Print.

Faloon, Kelly. "Enhancing Sustainable Design." Plumbing and Mechanical Feb. 2013: 30–32. Print.

Hardin, Brad, and Dave McCool. BIM and Construction Management: Proven Tools, Methods, and Workflows. 2nd ed. Indianapolis: Wiley, 2015. Print.

Kensek, Karen M, and Douglas E. Noble. Building Information Modeling: BIM in Current and Future Practice. Hoboken: Wiley, 2014. Print.

Knapp, Chris. "Forward History: Practice beyond BIM." ArchitectureAU. Architecture Media, 5 Apr. 2013. Web. 23 June 2015.

"New Research by McGraw-Hill Construction Shows Dramatic Increase in Use of Building Information Modeling (BIM) in North America." Dodge Data and Analytics. Dodge Data and Analytics, 11 Oct. 2012. Web. 23 June 2015.

Quirk, Vanessa. "A Brief History of BIM." ArchDaily. ArchDaily, 7 Dec. 2012. Web. 23 June 2015.