In the struggle to improve the process of designing and constructing better buildings, creating standards for software interoperability ranks as one of the most important battles. After a decade-long string of global meetings and conferences, a worldwide standard for data interoperability from one of the construction industry's most visible standard-setters is beginning to take hold.
Led by its chairman, Patrick MacLeamy, CEO of HOK, the International Alliance for Interoperability has made significant headway. Now a global standards-setting organization representing the spectrum of building stakeholders, from architects and engineers to software companies and building product manufacturers, IAI sprung from an August 1994 meeting of 12 U.S.-based companies joining together to make different software applications work together.
Today, the IAI says that its members are committed to exchanging information among all software platforms and applications serving the design, construction, and facility management community by adopting a single building information model. This mission is accomplished by defining, promoting, and publishing specifications for industry foundation classes (IFC) as the BIM and as a basis for AEC project information sharing.
In June 1995, the 12 founding companies demonstrated their first stab at software linkage at the AEC Systems Show in Atlanta. To open the work to the construction and facilities management industry and to software vendors, the group established the Industry Alliance for Interoperability. In the following months, chapters were established in Europe, Asia, and Australia (today there are 10).
At the first international IAI meeting in London in spring 1996, the global make-up of the group prompted it to change its name to the International Alliance for Interoperability. Further strengthening the organization, in May 2002, the North American chapter of the IAI merged with the National Institute of Building Sciences.
For over a decade, the IAI's industry foundation classes have been evolving into a system of data exchange structures that allows different AEC computer software programs to talk to each other and share information.
IAI issued the first full release of its IFCs in January 1997. Release 1.0 included support for some processes in architectural design, HVAC engineering design, facilities management, and cost estimating. The specifications limited its scope to a core model plus plug-in extensions to ensure structured extension of the IFC model with minimal disruption between releases.
Release 1.5.1, issued in July 1998, became the basis for the commercial release of the first three IFC-compliant software applications: Allplan from Nemetschek, ArchiCAD from Graphisoft, and Architectural Desktop from Autodesk. The applications were also the first to be certified by the IAI.
Issued in October 2000, release 2x marked a major change in the way IFCs are developed and released. It created a framework for the development of models that can progressively extend the range and capability of IFCs in a modular way. Projects develop models using the platform and then issue models independently as work is completed. An addition to IFC 2x is the ifcXML specification. This defines the complete IFC model in the XML Schema Definition Language (XSD) and provides an alternative approach to information sharing.
A year later, 13 applications were certified by IAI under Release 2.0. In November 2002, the IFC data specifications became an international standard: ISO/PAS 16793.
Fast forward to 2006. Three workshops have been held to test IFC2x3 certification: February in Berlin, May in Munich, and June in Budapest. Seven applications passed the certification in Budapest. The participating applications were Nemetschek's Allplan, Graphisoft's ArchiCAD, Bentley's Architecture, Autodesk's Revit, Tekla's Structures, Archimen's Active3D, and Solibri's Model Checker. The applications were tested against some 250 test cases.
Adding to the worldwide momentum for using IFCs was an August 2004 National Institute of Standards and Technology study that found that building owners, operators, and their allies could save at least $15.8 billion a year through better coordination of electronic data. The following month, an announcement by the U.S. General Services Administration's Public Building Service set a 2006 target date to start using standardized BIMs based on IFCs. GSA also contracted with IAI North America to help smooth the BIM transition.
According to Calvin Kam, GSA's 3D-4D-BIM program manager, there are currently six BIM software vendors working with GSA to extend the IFCs and incorporate new functionality into their products. At a GSA BIM workshop held in Washington, D.C., in early August, all six vendors presented their work. GSA also has a project that relies on IFCs to conduct 3-D energy simulation, which, according to an Autodesk representative, is the first working example of IFC development in the U.S.