Recall our very, very old 690 Folsom Street, previously a garage for executives at both 666 Folsom and 370 Third Street in the olden days. It actually didn’t look half bad next to the “brutalism” of 666 Folsom.

680 Folsom & 690 Folsom

But just like 666 and 140 New Montgomery, it has now been reborn.

John King of the San Francisco Chronicle has the scoop:

Futuristic S.F. cube building takes design risk in the right spot
By John King, Tuesday, December 16, 2014

In many corners of a city, wrapping a squat two-story box with an illuminated metal skin would be too much. Too weird in the day, a frozen static of flat metal strands. Too gaudy at night, a hovering cloud of colors and shadows.

But in the right setting — such as a heavily trafficked but visually drab corner behind San Francisco’s convention center — “too much” can translate to a welcome shot of well-engineered flash, as well as a tantalizing hint of what someday might sprout on our skylines.

If nothing else, it’s a change that’s hard to miss on the northeast corner of Third and Folsom streets, where a much-altered garage from 1926 at 690 Folsom is in the final stages of being reborn as a chic cube with office space above a retail-friendly ground floor.

To the north is a five-story 1980s parking structure, while across the way is a side view of the loading docks at Moscone Convention Center. In the rear is the recently completed upgrade of 680 Folsom, where the outer walls of concrete were replaced with a 15-story wrap of sleek glass.

Amid this drab, bulky terrain, 690 Folsom uses futuristic drama to catch the eye. Above a recessed glass-clad base floats a white box with an outer layer of white aluminum strips, a weave that slides in all directions.

Instead of a conventional facade, what we see resembles a spiderweb pulled tight around a box. On the east edge it doubles as an abstract artwork facing 680 Folsom’s raised plaza. On the north it turns the corner and trails off above a plaza designed for outdoor seating — the plan is to have ivy cover the exposed walls, so that the thicket of white dissolves into green mist.

Photo: Carlos Avila Gonzalez, The Chronicle

Photo: Carlos Avila Gonzalez, The Chronicle

Programmed design

Besides drawing attention to a corner that until now has never caused anyone to look twice, 690 Folsom is the city’s locally generated, mainstream example of parametric design — an aspect of computer-aided design where programs apply algorithmic modeling to a building’s form or surface.

Until now the tool has been used in San Francisco for marquee structures, such as the addition to the San Francisco Museum of Modern Art with its eastern side that evokes a weathered cliff. Here, the impact is on the skin rather than the shape.

Architect Charles Bloszies modeled different types of abstraction before one of the designers on his staff, Allie Roberson, fired up the computers to generate variations on the swirling porous theme. After one pattern emerged as the favorite, the computerized project files were sent to fabricators who used them to cut each of the aluminum panels, roughly 6 feet wide and 22 feet long, like (very elaborate) pieces of a puzzle.

Along the way, individual strands were removed or added with an eye to real-world durability.

“Something that looks cool on a screen might not work in real life,” said Bloszies, an engineer as well as an architect. “It would be like a shirt with too many holes hanging on a laundry line. Before too long it would start to sag.”

The best-known example of parametric design is the so-called Bird’s Nest that served as the stadium for the 2008 Beijing Olympics and shows the structural capabilities of shaping and engineering a building not bound by right-angle norms.

Local architects who work in a more conceptual vein use parametric tools to unfurl urban visions that would make a sci-fi movie seem tame. One firm, IwamotoScott , in 2009 conceived a 1,300-foot tower shaped like a sinuous upside-down Y as part of a speculative plan for Lower Manhattan sponsored by a business group there. With the San Francisco Museum of Modern Art as a client, Future Cities Lab devised a pier for the Embarcadero that it dubbed Hydramax — a cross between a porcupine and an amoeba that would house a fish farm and harvest water from fog.

Relatively simple

By these standards, the metallic tapestry at 690 Folsom is a melody played with one finger on a keyboard. Nor does it have the fantastical texture of local architect Thom Faulders’ facade for a mixed-use structure in Tokyo,where four patterns were compressed into two layers of white metal. The images show a porous skin that could be putty, pulled apart until it bubbles and breaks.

But in the real-life setting of urban America, at a car-clogged corner in a part of town that was off the map until recently, the show concocted by Bloszies for Boston Properties makes a statement nonetheless. It’s a billboard that advertises architectural imagination.

There’s thoughtful urbanism at work as well, which is essential.

Bloszies pulled the ground level along Third and Folsom streets back 7 feet from the existing sidewalks and the floor above, then replaced the thick concrete structural columns with round thin columns of stainless steel. On Folsom Street, the arcade flows into the steps that lead up to 680 Folsom’s public plaza.

These touches tie 690 Folsom into its surroundings, even as the upper-floor facade stands apart as a visual flourish.

Parametric design has real potential: It can be used to shape buildings that are fine-tuned to their surroundings with regards to energy use. Towers can be tweaked to lessen the downdrafts from winds that hit the upper stories.

Careful disruption

The danger comes if the quest for novelty trumps all else, with disruption on show at skyline scale. What looks cool to an edgy architecture student isn’t necessarily what enriches a city long-term.

On the 600 block of Folsom Street, for instance, I love the concentrated surprise of the webbed flurry against the poised glass slab above. Reverse the mix — turn 680 Folsom into a squat tower of tangled metal — and we’d be stuck with a strident gimmick in the air.

Ultimately, 690 Folsom hints at the vein of innovative design waiting to be tapped in this innovative region. But if and when this happens on a wide scale, the mind-bending architecture needs to be grounded in old-fashioned urban smarts.