The Next Dimension

Glaziers adopt 3D modeling tools for complex curtain-wall designs
Katy Devlin
November 29, 2013

3D modeling has opened the door to building designs that incorporate more complex curtain walls, with potential elements such as slopes, curves, bent glass, custom panel sizes and new material types. Oftentimes, these multi-faceted enclosures also call for several wall systems, each with unique requirements. These increasingly complex projects can present notable challenges to contract glaziers, and some firms are turning to 3D modeling tools to assist in the design and installation stages.

“The current project work hanging on the walls of our Advanced Technology Studios is fundamentally different than it was five, or even three years ago,” says Mic Patterson, vice president of strategic development for Top 50 Glazier Enclos Corp. “The dominant differences are shape and material. Geometric complexity is one of the ascendant trends in building facade design. Nonorthogonal form has long had a place in architecture, but Frank Gehry did much to popularize these sculpted forms, influencing the current propagation of nonlinear surfaces in the building skin.”

The newly opened Music City Center in Nashville exemplifies the complex curtain wall trend. The building features nine facade enclosure systems, including: unitized curtain wall, cable wall, AESS support systems, punched openings in precast panels, aluminum sunshades, louvers, metal panels, storefront, aluminum doors and glass handrails. The project also includes bent glass. Photos by Music City Center

These design trends are coming to life because of 3D modeling tools such as Autodesk’s Revit and Inventor. “These designs are being built now because of the tools that are available,” says Nick Bagatelos, president, Bagatelos Architectural Glass Systems Inc. “These tools are allowing for projects that previously could not be built, or would have been way too expensive to build. They are bringing those complex designs to fruition.”

As a result, glazing firms must “adopt true 3D modeling,” Bagatelos says. “For glaziers that want to do bigger projects, they need to adopt something like Revit. … About 75 percent of the work we do is design-build, and Revit in 3D is probably my most important tool to facilitate that.”

Patterson agrees. “3D modeling tools and techniques have enabled the dominant trend in building facade design towards greater geometric complexity,” he says. “The result is that 3D modeling is used at some level in virtually every project we do, and it is increasingly integral throughout the process from pre-sale concept development and estimating, through design development, production design, and fabrication.”

Indeed, complex curtain walls require collaborative planning between the design team and contract glazier to determine the most efficient, cost-effective system, and 3D modeling is an important component of that discussion, says Enclos’ Patterson. “Optimization processes provided by the facade contractors have become an important response to this increasing geometric complexity, as a means to rationalize the facade system, minimizing part types and system complexity without affecting design intent (and thereby controlling cost),” he says. “This typically requires early involvement with the design team, and is a leading reason we are seeing an upward trend in the employment of collaborative project delivery strategies like design-assist.”

Enclos Corp., served as the complete glazing façade contractor on the 1.2 million-square-foot center. Viracon, served as glass fabricator for the cable wall, providing 1 1/2-inch insulating glass units with two 1/2-inch layers of ultraclear glass and a 1/2-inch argon-filled airspace. Alexander Metals was the glazing subcontractor; Tubelite Inc. served as the entrance system manufacturer; and Linetec,, was the entrance system finisher. Oldcastle BuildingEnvelope was the glass fabricator for the entrance system. Kovach Building Enclosures designed, manufactured and installed all of the metal panels on the project. The architects were tvsdesign, with Tuck-Hinton Architects, and Moody-Nolan Inc. The general contractor was a joint venture team of Bell/Clark/Harmony Construction.

Enclos Corp. and Kovach Building Enclosures both used 3D modeling throughout the Music City Center project.

The benefits of 3D modeling tools go well beyond design, however. “We are actually embedding estimating information and scheduling information in the model,” Bagatelos says. “It is becoming a tool that we can use throughout the organization, instead of just a tool to look at design.”

The same 3D modeling software that allows for the design and fabrication of complex curtain walls can also serve as an installation tool. “Our glaziers, project managers can look at the 3D nature of the wall and get a better idea [of how to complete installation] just by looking at it,” Bagatelos says.

Currently, complex curtain-wall jobs represent a small, but important, segment of work. They are generally major projects, where the architects and owners are looking to make a unique statement with the façade. The 3D modeling tools that help make these iconic projects possible will become increasingly important across a wider variety of job types, Bagatelos says, and glaziers need to be prepared.

Katy Devlin is editor for Glass Magazine. E-mail Katy at