When James O'Callaghan, director, Eckersley O'Callaghan, presented the first design ideas to Steve Jobs for the Apple flagship store in SoHo, New York City, it featured all-glass stair treads paired with a metal rail system. Jobs responded, “I think you should make it all out of glass,” O’Callaghan recalled. And thus began Apple’s iconic and increasingly innovative structural glass stairs and storefronts.
Attendees at the BEC Conference yesterday in Las Vegas were treated to a tour of the evolving innovations in glass at Apple, where designers and engineers continued to push the envelope of what is possible in glass design.
From the beginning, the idea was “a very simple structure,” O’Callaghan described to the group of about 400. At each step, and in each new store, “we began to strip away the levels of connection. … Each time, there is a small incremental change.”
That first location in SoHo featured the all-glass stair rail and treads, with minimal hardware. A location designed soon after in Los Angeles includes a stair that can meet significant seismic loads. “The stair is hung rather than supported at the base, and it can accommodate lateral sway,” O’Callaghan said.
Next came longer staircases (a 5-meter stair in Beijing), and circular staircases, like that in Osaka. “This required chemically tempered glass,” O’Callaghan recalled. From single-story circular staircases came two-story staircases (14th St. in New York).
In 2006, the company moved beyond stairs to develop a glass cube entrance to the 5th Ave. underground store in Manhattan. However, the dimensions of the cube—30 feet on each side—required 106 panels and 250 primary fittings, and thus more interruptions in the clarity of the space.
So, the design team began investigating ways to get larger glass lites, requiring fewer connections. “We were looking for large format glazing applications where we [could] maximize transparency and minimize fittings,” O’Callaghan said.
Working first with seele, which bought a 15-meter autoclave, O'Callaghan's designs began to feature much larger lites of glass. “However, the logistics associated with such large lites were quite challenging. There were no machines to lift the glass, or to ship the glass,” O’Callaghan said. Beijing North Glass also made large investments in equipment to produce the large lites for Apple, including developing a tempering machine to handle 12- to 13-meter curved glass for the glass drum at Apple IFC Shanghai.
With large format glass now available, the company began exploring glass railings made of one lite of glass, like that used at the Hamburg, Germany Apple Store. And, in 2011, it refurbished the 5th Ave. glass cube with the large glass, totaling just 15 panels and 40 fittings. “There is a certain elegance when we start to strip down the connections,” O’Callaghan said.
The newest developments in glass for Apple include glass walls that act as structural support for the roof structure. The company completed a store in Palo Alto, California, where glass columns support a steel roof. And, the new Apple store in Istanbul consists of just four massive panels of glass that are joined at the corner with silicone joints and topped with a carbon fiber roof. “It’s drilled down to the minimum. It’s almost not there. This is a successful conclusion regarding where we are trying to drive design,” O’Callaghan said.
And of course, there are the large-scale architectural feats on display at the now under construction Apple headquarters.
Looking ahead, O’Callaghan says even larger lites are coming, with 4 meters by 20 meters now possible. And, he sees great architectural possibilities with Corning’s Gorilla Glass, an ultra-thin, ultra-strong glass. “This is different than float glass. We are able to use a cold bending method to create new forms. It’s something that can be a flexible material on the skin and used to create more lightweight structures,” he said.
Katy Devlin is editor of Glass Magazine. Contact her at firstname.lastname@example.org.