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While 2D CAD merely automates the familiar work of hand drafting, CAD objects represent a new, more intelligent representation of buildings and building components. The real power of objects lies in their ability to present virtual buildings—just like physical objects, CAD objects have attributes and behaviors, such as the handedness and swing of a door. However, interoperability among different programs is far more problematic for complex CAD objects than it is for simple 2D lines. This is where IFCs come in—a system of definitions for classes of objects, such as doors, walls, and stairs. If two or more programs, such as space-planning software, a CAD tool, and a cost-estimating package, all comply with the same IFC standard, then they can use and operate on each other’s model data.

Since its founding in 1995, IAI has released several versions of IFCs. While many of IAI’s 600-plus member software firms chose to wait for the most recent IFC 2.x before integrating the standard into their wares, a significant number of IAI members, operating separately under the banner of Building Lifecycle Interoperable Software (BLIS), chose to get a head start by incorporating the earlier IFC 2.0 standard into their products. For example, a space-planning spreadsheet in Microsoft Excel can be converted to a simple floor plan in Microsoft Visio and then turned into a 3D object CAD model in Graphisoft’s ArchiCAD—all through the interoperability features of IFC 2.0, without file conversions or reentry of data. Timberline’s IFC 2.0-compliant CAD Connector can then use the data in the ArchiCAD model to quantify building assemblies for Timberline’s Precision Estimating package. Dianne Davis, president of AEC Infosystems, a CAD consultancy and ArchiCAD dealer in Baltimore, sees the BLIS initiative as “taking the technical interoperability of IFCs and building the business case of company-to-company connections around them.”

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Recently, several major CAD vendors, including Graphisoft, as well as Autodesk (Architectural Desktop), Bentley Systems (Microstation Triforma for Architecture), and Nemetschek North America (VectorWorks Architect) agreed to move forward over the next three years with implementations of IFC 2.x comparable to what the BLIS project achieved with IFC 2.0. Even previously IFC-aloof Revit Technology joined in the announcement, possibly under the influence of the firm’s pending acquisition by Autodesk. However, ArchiCAD is thus far the only CAD product to incorporate support for both the NCS and IFC 2.0 in the same program.

Playing tag

Because IFCs support the ability to move data via “tags,” or descriptors, in the Web language XML (Extensible Markup Language), standards enthusiasts such as Tardif at the AIA foresee an opportunity to add XML tags to NCS drawing entities so they can be integrated more easily with IFCs. “The goal of converging NCS and IFCs is to get an interconnected set of 2D and object representations for the same data,” he says. Facility owners and managers have a keen interest in this integration, Tardif notes, adding that entities like corporations, universities, and medical facilities “do not want to develop and maintain their own drawing and object standards, and they don’t want to integrate or translate between 2D standards and object standards. They just want to receive standardized data.”

ArchiCAD is the first product to implement and integrate both the object-based IFC 2.0 standard and the 2D-based National CAD Standard. a trend likely to be followed by other vendors that have recently committed to IFC 2.x.

David Jordani, FAIA, agrees. His company, Jordani Consulting Group, in Minneapolis, helps large organizations such as General Motors and the University of Minnesota manage their facility information. “Owners still have to confront the dominance of legacy information—2D drawings for hundreds of millions of square feet of space,” he says. “NCS provides the continuity and consistency for drawings, but companies moving to object models like IFC need to manage their migration and be committed to maintaining the extended value of the model data. Using some form of XML will smooth that process.”

Shaw at NIBS is hopeful that intermediate steps such as XML will help bring the NCS and IFCs closer together, because that path leads to the utility owners need from their facility information. “After the first release of NCS, NIBS changed the committee name from CAD Council to Facility Information Council (FIC),” says Shaw. “That group still develops NCS, but it also does outreach to the IAI and to the OAA [Owners’ Association Alliance, a confederation of real estate and industry groups].” A subset of the FIC, the Facility Maintenance and Operations Committee, is preparing to release an XML schema that plugs into IFCs and also allows building equipment manufacturers to publish operating manuals in electronic form that can be read directly by computerized maintenance management software used by owners.

Stirring the alphabet soup

Folks outside the Beltway are easily overwhelmed by the proliferation of TFLAs (three- and four-letter acronyms), but they provide a convenient verbal shorthand for communicating complex issues. As both the NCS and IFCs blossom, with cross-pollination by various forms and flavors of XML, it is clear that FIC and IAI will grow closer together. NIBS will spread an expanding umbrella over the activities of AIA, CSI, OAA, and other interested parties.

This near-cryptographic complexity will benefit architects by increasing the value of the design data we create and extending that value both upstream, toward predesign planning services, and downstream, toward post-occupancy management services, within the total facility lifecycle.

No matter how you mix and match the acronyms, that formula spells success.