BIM Streamlines, and Blurs Lines
Laptop perched on a café table, David Fano scrolls through a presentation he normally shows to his Columbia University architecture students, who are already preparing for digital practice. The screen displays black-and-white elevations, blue wire frames, and rendered models, all drawing types that can be realized with building information modeling, aka BIM, and programs like Revit Architecture, ArchiCAD, and Vectorworks. For Fano, a New York–based consultant specializing in BIM implementation for design and construction offices, BIM embraces everything from parametric modeling to CAD details. It's a big, powerful way to think about the design delivery process. Under BIM, the traditional phases—schematic design (SD), design development (DD), construction documents (CDs), and construction administration—get streamlined and integrated.
A $78 million project designed in Revit, the Almac corporate headquarters began construction in July and is expected to finish in May 2010. Project leader Jim Daly of Francis Cauffman Architects prepared the diagram above to illustrate how BIM blurs the lines between the traditional phases of the design process (note how SD, DD, CDs, and build-out substantially overlap) and allows for early bid-package issue, among other changes.
To illustrate BIM's benefits, Daly created a time line (left) for the 70,000-square-foot, three-story Pennsylvania headquarters Francis Cauffman has designed for Almac, a pharmaceutical company. The diagram shows overlap between the SD, DD, and CDs phases. The final building footprint and interior programming are fixed in the first stages of the model. With the Revit model coming together midway through design development, the architectural team was able to issue pre-bid steel, mechanical, electrical, and plumbing packages well before the traditional milestone. An integrated model leads to a more streamlined project, and with fewer RFIs and change orders, there's potential for owner cost savings.
The potential for more efficient architecture is huge, but at the time of the 2006 AIA Firm Survey, only 16 percent of AIA member–owned architecture firms had BIM software. That number is rising alongside rapid changes in the technology. A paradigm shift is occurring in the profession: On Oct. 17, the AIA issued "E202–2008 Building Information Modeling Protocol Exhibit," a contract document written by industry practitioners that, according to the press release, "sets the requirements and authorized uses for BIM content, and identifies BIM authors at five progressive levels of development. It also establishes protocols for model ownership, conflict resolution, storage, viewing, and archiving."
Such protocols should help settle questions over who owns what information at what point. A common complaint is that contractors haven't been quick to adopt BIM. Still, Fano has some lingering doubts that design professionals are ready to get up to speed, saying,"If architects don't take a more active role in BIM, contractors will own this aspect of building." And just as the words are out of his mouth, he outlines some of the fears that go along with adopting BIM. "There is a feeling that it will hinder the design—that you can't be as free. That it will force the architect to make decisions too early." Then, he softens the blow: "It's just a tool," he adds.
Because BIM software packages like Revit and ArchiCAD are capable of linking detailed product information to the model, they make it possible to keep track of project costs and material takeoffs. Fano brings up a façade drawing of a housing project on his laptop. (He produced it while an employee at SHoP Architects.) The façade is composed of three kinds of panels, each a different material. To control the cost implications, he varied the pattern and got "live" takeoffs, ultimately performing a type of self-imposed value engineering well before the drawings landed in the hands of the construction manager. Daly, however, is lukewarm on this aspect of BIM: The information that manufacturers embed in the files is surplus, he feels, to architects' needs.
It is hard to understate BIM's impact on a design delivery process that hasn't really changed in a century. Firms that have switched to BIM don't switch back, but the technology comes with tensions and reservations. "The single greatest concern I've heard is fear about perceived difficulty of implementation. It is true that every firm that has adopted the technology has gone through a learning curve; this is a fact of adoption of any new technology or technique," remarks AIA resource architect Markku Allison. "Other concerns include cost (of both initial software and training), difficulty in finding team members who are also using the technology, and the possible blurring of boundaries through sharing work on a model."
This blurring between construction management and architecture, at its best, results in collaboration, but there is also fear of a power grab for project control, with the architect marginalized. To address the issue, the AIA in November 2007 released the Integrated Project Delivery (IPD) Guide. The document outlines best practices for collaboration between owners, designers, consultants, and contractors, with BIM as the underlying technology.
While there still are some pretty significant kinks regarding insurance and liability, the holistic promise for efficient, sustainable projects shines bright. "With the traditional process, we are constantly defining boundaries; with IPD, we have more time to design the project," says Allison, who was part of the multidisciplinary team that drafted the IPD Guide. "Other stakeholders can bring their skills to the project. Each can contribute in a richer, more meaningful way."