Byline: catherine fox, Staff date

Like a teenager hitting puberty, Atlanta is growing up. Fast.

Reflecting the sort of urban renaissance occurring across the country, cranes hover above building skeletons and half-clothed structures clustered on Atlanta's multiple skylines. Since 2004, some 16 towers have sprouted in downtown, Midtown and Buckhead, according to skyscraperpage.com, a 10-year-old global forum on the topic. The site lists more than 25 others under construction here, and 50-plus in the proposal stage.

This new generation of towers promises to change more than the city's skyline. As one might expect of an adolescent growth spurt, Atlanta is filling out, too. Or maybe it's filling in. After years of emulating suburbs, the city and its citizens are recognizing the virtues of density, mixed-use and transit-oriented planning.

Buzzwords like "human scale" and "pedestrian -friendly" have become realities, thanks in large part to zoning codes that mandate street-level storefronts and the like. An exemplar of this change, Blueprint Midtown's guidelines spawned the synergy of residential high-rises, cafes and shops, and it's making the district a vibrant community.

Similarly, developers who have assembled large parcels are thinking in terms of building coherent ensembles. When Barry Real Estate Cos. President Chris Schoen invokes Rockefeller Center as the model for Allen Plaza at the north end of downtown, it gives one hope that the reign of the skyscraper as a lone object in the landscape -- the 1992 Bank of America Tower, for example -- is over. Up the road, Cousins Properties' Terminus in Buckhead will be a 9.9- acre village in its own right, and its curb appeal should contribute to the vision of Peachtree Street as a promenade rather than a thoroughfare.

The new construction is bringing more changes. Eco-responsibility, for one. Energy-saving design and devices are becoming de rigueur. LEED certification -- a rating system that is the national benchmark for high-performance green buildings awarded by the nonprofit U.S. Green Building Council -- is a badge of honor. Better design is another, as savvy clients are demanding higher quality. Though cities like Chicago that have traditionally been more architecturally sophisticated than Atlanta remain so, we are beginning to see a new maturity. Sculptural forms, careful proportions and textural richness characterize the best of the new crop.

And Atlanta is going mod. The majority of the city's new skyscrapers are constructed of glass, steel and concrete, fashioned crisp and sleek.

There is an economical imperative behind this fashion. Curtain-wall construction, which allows for larger, more open floor plates, offers tenants flexibility they need in fast-changing times.

But psychology plays a role as well. Just as teenagers inevitably disdain their parents' fashion choices, the masonry and historical ornament of the 1980s and '90s now seem so last generation.

The success of the concrete condos geared for a young demographic that Novare Group introduced in Midtown solidified the notion that modernism is hip.

This despite the fact that modernist architecture is almost certifiably antique, and that its self-definition as the path to utopia is long discredited.