In a city famous for its views, the one from the observation tower of the year-old De Young Museum is among the best, stretching from the Pacific Ocean to the distant Berkeley hills.

Though most of the visitors are too busy snapping blurry cellphone pictures of the Golden Gate Bridge to notice, it’s also an unusually good place to consider one of the most dramatic shifts to hit the architecture world in decades: the growing prominence of the roof -- and, perhaps more important, the top-down perspective that exposes it to view -- in the design of buildings, neighborhoods and even whole cities.

Thanks in part to the surging popularity of Google Earth and other Web-based programs, which give the public a bracingly new, if detached, way to interact with the built environment, rooftops are shedding their reputation as forgotten, wind-swept corners of the urban landscape and moving toward the center of architectural practice.

The nascent rooftop revival is visible in three very different forms from the De Young tower. Looking straight down you can see the roof of the museum’s main wing, which is covered in long, thin skylights and the same copper panels that wrap the rest of the museum. Knowing it would unfurl prominently beneath the tower, the De Young’s Swiss architects, Jacques Herzog and Pierre de Meuron, gave the roof extra attention.


Directly to the south is the site of the new $429-million home for the California Academy of Sciences, designed by Italian architect Renzo Piano. When it’s finished in 2008, the academy will be topped by an undulating, 2.5-acre green roof, planted with wildflowers and other native species -- a remarkable piece of landscape architecture lifted 35 feet into the air.

Turning away from the windows, finally, you encounter a huge satellite photograph of San Francisco, picked specifically by Herzog and De Meuron and covering an entire wall. At the center of the image is a copper-colored speck: the museum. The photograph offers a wry twist on the idea of the observation tower in an age of digital technology and pervasive surveillance -- a reminder that while you are looking down on the world, the world is also looking down on you.

Thanks to a flurry of interest in the top-down view, architecture is full of such moments these days. Environmentally minded firms are making dramatic use of green roofs like the one Piano developed in San Francisco, which can help insulate buildings and reduce polluted storm runoff.

And in many of the world’s biggest cities, increasing density means occupants of one building are more likely than ever to look down on another. The pair of towers Frank Gehry is designing on Grand Avenue in downtown Los Angeles will overlook not only new retail pavilions but also the architect’s Walt Disney Concert Hall across the street.


“It’s an issue in Brooklyn too,” Gehry said, referring to his design for the $4.2-billion Atlantic Yards development, which will include more than a dozen tightly packed towers.

And then there’s Google Earth. Using satellite images and aerial photographs, the program and its competitors, including Microsoft’s Virtual Earth and Live Local, have enabled a new kind of architectural tourism, allowing Web surfers to zoom around the globe to see how buildings by Santiago Calatrava or their own houses look from above. According to Google Earth director John Hanke, more than 100 million people have downloaded the free program since its April 2005 debut.

“Our idea has been to democratize access to views of the places where people live and work,” Hanke said.

The program, developed by a small Silicon Valley firm called Keyhole that Google acquired two years ago, remains a work in progress. Only a third of the world’s cities are shown in high-resolution imagery, and a number, including Los Angeles, are represented by clearly outdated views. But if you view the images of a city that has been updated recently, such as London, the images are startlingly crisp.


The forgotten facade

To tour a typical American downtown with Google Earth is to see a collection of roofs that either sit forlornly empty or are littered with rusting mechanical equipment -- a lack of architectural attention that can be traced to the rise of the Modern movement a century ago. Modernist dogma, by insisting that roofs be flat, robbed urban buildings of the handsome ornament and geometric forms that grace the top of New York’s Chrysler Building, L.A.'s Central Library and other landmarks.

The irony of that development is that many Modernist architects were obsessed with the roof and what to do with it. The Swiss-born architect Le Corbusier, in fact, wrote extensively about the potential of the rooftop as a building’s “fifth facade.”

New York, Chicago and other crowded cities have grown more aggressive in exploiting that underutilized space; even Los Angeles has a few popular rooftop spots, such as the Standard hotel downtown. But the shift now emerging will have ramifications far beyond the addition of a penthouse bar or pool.


In his design for the 1,300-acre Orange County Great Park, New York landscape architect Ken Smith included a giant helium balloon, painted bright orange, that will lift two dozen visitors at a time 500 feet into the air. The balloon is meant to act as a visual icon for the park, visible from nearby streets and freeways. It will also give its passengers a sprawling view of how the park is laid out -- in essence, allowing them to look down on a design blueprint at full scale.

Smith worked with similar themes in a design for a new rooftop garden at the Museum of Modern Art in New York. When the garden opened early last year, some were surprised to discover not only that it was composed entirely of synthetic materials, including plastic rocks and rubber mulch, but also that it was inaccessible to museum visitors and even staff.

But those groups weren’t the intended audience. The garden was designed almost entirely for the benefit of the residents of the high-rise condo towers that surround and overlook the museum.

“From the beginning, we thought of it strictly as a top-down design,” Smith said.


Architects say the influence of the bird’s-eye view seems to grow by the week. Clients arrive for preliminary meetings having studied overhead views of their building sites on the Internet. And if you sit in on thesis reviews at an architecture school these days, chances are quite good that a student presentation will begin with an image from Google Earth or another online source.

Earlier this year, Google bought a design program called SketchUp and incorporated it into Google Earth, allowing architects to move quickly from an overhead photograph of a building to a three-dimensional digital rendering of it.

“My students use Google Earth obsessively, especially now that it includes SketchUp,” said Paul Preissner, a Chicago architect who is teaching this fall at the University of Nebraska.

Prominent structures have long been seen from the air: Think of the blimps that hover over college football stadiums on Saturday afternoons. And Los Angeles is familiar with the bird’s-eye perspective of a televised police chase. Thanks to the Web, the public can now bring the same kind of scrutiny to almost any building at any time.


There is a significant political dimension to that shift. The overhead view has always been synonymous with power. Indeed, many satellite images in Google Earth were once available only to government agencies.

“For me, Google Earth is revolutionary in that sense,” said Enrique Norten, a Mexican-born architect based in New York. “Even a year or two ago, it was a huge problem just to get a single aerial photograph for a site. And you had to pay for it.”

But there are reasons to be less sanguine about the implications for architecture and urbanism. Precisely because it is so easy to use, Google Earth suggests a kind of access to cities that can’t be matched in the real world, especially after the attacks of Sept. 11. It may tempt architects to play to their growing virtual audience at the expense of a building’s day-to-day users, creating new architectural icons designed to look striking not from the sidewalk but from above, on a computer screen.

And the technology may promote a false sense that cities are somehow knowable at a glance. The power of that illusion has become clear on cable news programs, whose anchors use satellite imagery to zoom in, godlike, on the site of a story.


Top-down design

Some designers and planners are already combining iconic design and the top-down view. Dubai, in the United Arab Emirates, has dredged up huge swaths of its waterfront to make room for luxury housing developments. Among the best known is the Palm Jumeirah, a man-made island that fans out into the Persian Gulf. Seen from the air, it makes up a palm-frond pattern that has become a de facto logo for a newly ambitious Dubai.

The Dutch landscape architecture firm West 8 won a competition this summer for Toronto’s waterfront with a plan calling for a floating island in the form of a maple leaf -- a graphic element borrowed from the Canadian flag -- that will be visible from the top of the nearby CN Tower.

Such projects herald the emergence of a new, hybrid brand of urban planning, one that mixes elements of highly marketable, camera-ready design, earthworks (such as Robert Smithson’s Spiral Jetty in Utah) and the perspective made possible by Google Earth.


It’s difficult to ignore the fact that the approach to design that works best in that framework is muscular and grandly scaled. Santa Monica architect Thom Mayne’s recent proposal for a state park at the so-called Cornfield site near downtown L.A., a deliberately provocative plan created with the landscape firm Field Operations, calls for a new Dodger Stadium on the edge of Chinatown and housing on the stadium parking lot. The design team’s overhead renderings only furthered the sense that Mayne was moving around huge chunks of the city like chess pieces.

In beginning to grapple with the effects of technology on the design world, architects have fixated on the fluid, “blobby” shapes made possible by powerful software. But Google Earth suggests the most significant result of the marriage between architecture and computer power has to do with perspective rather than form.

What’s changing most radically, in other words, is not how buildings look but how we look at buildings.

christopher.hawthorne@ latimes.com