The presentations at the meeting can be segmented into ones that deal with design or technical issues. On the design side were presentations by a number of architects. 

Mark DuBois, Ohlhausen DuBois Architects, New York City, presented a case study of glass being used as an unbraced, primary load bearing element in a residential project in Santa Fe, N.M., creating a pure wall of glass that would seamlessly integrate with the architecture. The wall measures 3.5 meters high by 8.6 m in length and transfers the loads from a steel framed roof into a concrete foundation.

“The testing for the project was an eye opener for me,” he said. A full-size panel and a series of smaller test panels were tested. “The design and execution of the testing procedure was time consuming and had significant cost,” he added.

At the construction phase, DuBois said, “We had to deal with local metal fabricators who were not very sophisticated, so there was a lot of back and forth and handholding to get what we wanted.”

DuBois found few glass fabricators that both reach out to architects and are willing to do these custom jobs. “Dlubak was the only one enthusiastic to take on the project.”

The result, he said, was profound. “It makes people rethink what the purpose of structures is. It does not demand attention. It does not scream, ‘I am a very sophisticated glass wall.’

The panels are relatively narrow but I like that because it emphasizes their verticality. There are also some logistical issues about wider panels,” he added.

Keith Boswell, a partner in the San Francisco office of Skidmore, Owings & Merrill, discussed a “detail and design idea that we have been considering for four or five years about how we would like to turn the corner.” The corner discussed is part of the design for a museum in the Bay Area. 

Boswell said he had never liked the look of two pieces of glass coming together with a bead of sealant. Nor did he want the two pieces of glass to just butt against each other. Instead, he is looking for bent tempered glass with a very tight tolerance that does not require sealant. “I contacted a number of fabricators and they either hung up on me or said it could not be done. But I got one on the phone and when I heard it couldn’t be done, I asked if it could not be done or if it just had not been done,” Boswell said. To date, there has been no resolution to the dilemma.

Glass Apartments
Ian Richie, who has been using glass as a structural element for 35 years, gave a presentation on the design of the all-glass apartment complex at Potters Fields, which is adjacent to Tower Bridge and opposite the Tower of London. In its final design, the building has a glass veil. He said architects often don’t think about reflection and how it affects a structure’s neighbors, but in this case the reflection off the façade creates a lighthouse type of effect.

He discussed the impact energy regulations had on the development of the project and how the regulations kept evolving which meant the design had to evolve even though they had anticipated change. “Legislation often pushes standardized solutions,” he said. “If I just follow legislation, my brain switches off.”

Another observation he made, with a touch of glee, based on the experience of this project, related to the role of the developer and insurance. “The insurance companies and façade consultants had grown up together,” he said. “The consultant was needed by the insurance company.”

David Cormie, Arup Security Consulting, discussed bomb blast performance of glazed facades. He said that the UK-based company is working on major projects on five continents. “Terrorism has changed and been expanded to many areas of the globe,” he explained. “Antiterrorism construction allows a structure to stand out from the crowd.”

In U.S., he said, blast performance is based on strength not flexibility; the capability of the unbroken lite only. “Arup prefers flexibility and ductility. In the UK, design of laminated glass as a flexible membrane represents the basis of most blast-engineered glazing design,” he said. If the glass is too thick and the capability of the bomb is stronger than the glass, the PVB interlayer can tear and the glass comes out of the frame, he said.

One of the things which makes GPD so interesting is that you can attend a session discussing a project that utilized point supported glass with drilled holes in it and then move to another session that discusses the same technology—without holes. And a lot of people did just that. 

Hole-y Smokes!
Stanley Yee of Facade Group Inc., provided in-depth details on construction of the wall at the new Bangkok International Airport, which utilized heat-strengthened point supported laminated glass with holes. He was followed by a presentation by Barbara Siebert, a structural engineer who has her own consulting firm in Germany, that discussed new technology she has been involved with for point fixing glass in a facade without drilling holes in the glass.

The Bangkok airport project, the largest point fixed heat-strengthened glass wall in the world, was designed by Murphy-Jahn, Chicago, and opened last September. Yee described in-depth the glass selection process for the project and the testing which had to be done for the construction.

The glass is fixed to the spider via holes in the glass, and the problem was that there was limited test data for the system as it was designed. However, after a series of testing it was concluded that holes can be drilled in heat-strengthened glass, Yee told attendees.

Siebert explained that the holeless design was inspired by the traditional technique of Japanese timber construction. “A simple technique was transferred to glass and stainless steel,” she said. Laser technology is used for the design which was utilized on the Porsche Museum in Stuttgart. “Small stainless steel cantilevers are used inside the fitting for the dead load,” she said.

Sessions like these give the architect, designers and others involved in the construction information that was learned through this project that they may be able to apply to their own work. 

Architects' Guide to Glass & Metal
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