NEW YORK - Wearing a flawlessly pressed white dress shirt, navy slacks and hard hat, Philadelphia architect James Timberlake hoisted himself onto an aluminum beam of his firm's latest construction project, a four-story, see-through, energy-efficient plastic house. The pioneering creation, improbably wedged among the skyscrapers of 53d Street, is about to change everything for his firm, KieranTimberlake Associates.

Dubbed Cellophane House, the structure is one of five full-size houses commissioned by the Museum of Modern Art for its summer show, "Home Delivery" - a major survey of the state of house-building - and erected on an asphalt lot two doors west of the museum. KieranTimberlake managed to complete its contribution in a breakneck 16 days, in full view of the passing throngs, by applying the techniques of Internet-age manufacturing.

Once the exhibit opens Sunday, the house will be seen and visited by many more people - museumgoers, architecture aficionados and art critics. If they don't know the Philadelphia firm's name now, they will soon.

The high-profile exhibit caps an extraordinary run for KieranTimberlake, which operates out of a big loft in the Spring Garden neighborhood. In the last dozen months, it has been named firm of the year by the American Institute of Architects, included on a select team by actor Brad Pitt to help rebuild New Orleans' Lower Ninth Ward, and showered with international acclaim for its ultra-green Loblolly House on Taylors Island, Md.

MoMA architecture curator Barry Bergdoll picked KieranTimberlake from 500 applications - and that, he adds, was "before they were firm of the year, before New Orleans."

"It's pretty heady stuff," admits Timberlake, who was racing around his office last week with partner Stephen Kieran, trying to untangle last-minute snafus.

The fancy Italian kitchen they ordered for the house - an indulgence, yes, but a sustainable one - was still sitting on a ship in New York Harbor, waiting to pass through customs. The photographer assigned to document the project had yet to submit photos of the finished house. Meanwhile, other clients clamored for attention.

Still, as Kieran reminded himself while flipping through the construction photos from the last three weeks, "this house didn't even exist as an idea 12 months ago." Tomorrow the comfortable, livable house will open its doors to journalists and museum members.

Covered in a gossamer sheath of clear, recyclable PET plastic - the stuff of water bottles - and embedded with all the hardware and photo-voltaics necessary to operate off the grid, the Cellophane House immediately makes the four other, wood-based houses on MoMA's lot look so 21st century. (It's not all high-tech, though: Cellophane comes with a roof deck that cries out for a summer cocktail party.)

The MoMA show is more than just another feather in KieranTimberlake's cap. Cellophane House gave the firm a chance to distill two decades' work and architectural thought into a single project. The two-bedroom, two-bath house is part demonstration project, part art object, part manifesto. It offers a more environmentally responsible way of making buildings that still have the comforts we cherish.

"I hope that people will look at this house as a glimpse into the not-too-distant future, as to how we might live," Timberlake says. "It's certainly not a Toll Bros. house."

While the home-building giant is hardly averse to KieranTimberlake's time-saving construction methods, it's unlikely Toll Bros. would dare construct a house whose walls, floors and roof are almost entirely see-through.

Some viewers may assume that Cellophane's translucent, circuitry-studded PET sheets are meant to be instructional, left clear so viewers can understand the house's inner workings. But the architects really do envision a day when the only barrier between inside and out, between the safety of shelter and the uncertainty of the elements, is a thin plastic membrane.

"We're programmed to think a wall has to be stiff," argues Timberlake. "We've redefined the wall. It's not something solid. It's not a flat surface, with gaps punched in for windows. We're saying a wall is seamless. We want to get out of the conventional notion that a window and a wall are two different things."

Might that make some occupants uneasy? Sure, he admits, "but 50 years ago, people said you couldn't live in a glass house." Now condos with floor-to-ceiling windows are the rage.

It's not just that their design looks like no home you've ever seen before. How it was built is even more radical.

Disenchanted with the construction industry's slow-moving, wasteful methods, in which buildings are assembled sequentially, piece by piece, the architects' goal is to reinvent the way we build. They have applied the same software and methods that make it possible for clothing and car companies to turn around new designs in a matter of months.

Although the result sounds straightforward, it's been a long road for the two architects, who labored below the radar for years, mostly doing well-regarded but unheralded university work. Kieran, now 56, and Timberlake, 55, met while working for Robert Venturi and Denise Scott Brown, Philadelphia's most important architects, but grew frustrated in that highly theoretical firm. "We wanted to build," says Timberlake.

They broke off in 1984, after returning from fellowships in Rome. But it wasn't until they designed a green classroom building for Bryn Mawr in 1993 that they began to think hard about the intersection of the construction process and the environment. Taking a design cue from Chairman Mao's Little Red Book, in 2004 they published their own red-covered revolutionary manual, Refabricating Architecture, laying out many of the ideas that are the basis for Cellophane House.

For the MoMA project, they created a complete 3-D model of Cellophane on a computer, detailed down to the electrical outlets. The model was e-mailed to their fabricator, Kullman Builders, in Lebanon, N.J., who sliced the model into logical "chunks," built the sections in the factory, and shipped them to MoMA on a flatbed truck.

The staircase came in one chunk, an entire bathroom in another. Since the computer model gave the precise length of every beam and surface, there was almost no waste. Conventional builders send almost 40 percent of their materials to the landfill.

KieranTimberlake's process not only reduces trash, it saves time. Once the sections arrived on site, Cellophane went up in less than three weeks. The parts fit together perfectly; workers only had to snap and bolt them into place. While some of the other crews were still frantically assembling their houses, Kieran and Timberlake had time to do leisurely interviews on MoMA's lot with the Discovery Channel.

Still, their smooth finish hasn't kept them from worrying about how Cellophane House will be received, especially in an age besotted with unusual, iconic forms. As Kieran explains, their rectilinear house isn't a "style statement, part of the current fetish with glass and glazing." Bergdoll says their house may appeal more to the cognoscenti.

It certainly does to Kevin Angstadt, a partner at Philadelphia's young and edgy QB3 design, who has followed KieranTimberlake's evolution with admiration.

"It's their process that makes them so compelling as architects," he says. "They've taken on the whole construction industry . . .. They're the gold standard in Philadelphia architecture."

See a time-lapse video of the Cellophane House rising at

For more on the MoMA "Home Delivery" show, visit http://go.philly.com/moma

Contact architecture critic Inga Saffron at 215-854-2213 or isaffron@phillynews.com.