In recent years Building Information Modeling, or BIM, has gone from being a cutting-edge new technology deployed on particularly challenging projects to an accepted part of the builder's toolkit on every job. BIM refers to a suite of technologies and techniques that taken together allow builders to do their job faster, more accurately, with fewer disruptions, and with lasting benefits for our clients.
From Blueprints to CAD to 3D Design
The evolution from pen-and-paper blueprints to computer aided design (CAD) represented a revolution in architecture. CAD, however, is basically a computer tool for drawing 2D blueprints, while 3D design is taking the creation of buildings into a new dimension: structures are designed from the start as three-dimensional models. The software can export construction documents for the people who will actually build the structure.
High-Tech Solutions for Challenging Buildings
Hoffman pioneered computer-aided 3D design on projects like the Experience Music Project and Seattle Central Library. In 2000 Hoffman worked with architect Frank Gehry to build his revolutionary curvilinear design for Paul Allen's EMP; the complex building skeleton of curved I-beams would have been almost impossible without CATIA, a 3D design package originally created for the aviation industry. In 2004 we built architect Rem Koolhaas' design for the Seattle library, modeling the thousands of structural members and joints in Xsteel.
Every project can benefit from the sophisticated 3D techniques that allowed Hoffman to build the EMP. By modeling every building system in three dimensions, plans are coordinated to make sure that mechanical and electrical systems don't clash with each other, or with the building's structural systems. Engineers can even "fly" models of complete systems through the building model to plan a route to take when installing particularly bulky pieces of machinery.
Databases & As-Builts: Lasting BIM Value
BIM is a lot more than just a 3D drawing table. Every component of the modeled building's systems exists in the plans as a discrete object with its own data attached – data that can include its technical specifications, part number and manufacturer. The model can become a 3D database of everything in the building, an invaluable resource for the owner for everything from routine maintenance to future expansion and remodeling projects.
3D Laser Scanning
One of the most revolutionary new BIM tools is the 3D laser scanner, a device that can take a three-dimensional picture of the real world for import into computer models. The scanner sends out millions of pulses of laser light, measuring the time it takes each to return; the result is a "cloud" of millions of points of 3D data; scans from multiple locations become a complete 3D image. At the Seattle Central Library, regular laser scans were used to make sure that construction matched the plans. And on recent renovation projects, laser scans have been used to create accurate as-built models of older buildings.
For a Closer Look at Building Information Modeling: