While Rincon Hill’s steep glass towers have reshaped San Francisco’s skyline — for better or worse — new and equally large residential compounds make their mark by hugging the terrain.

But keeping a low profile doesn’t lessen the impact on their surroundings, as three horizontal but super-sized complexes make clear.

Each tops off at six stories and is packaged deftly by the architects to keep things interesting. Each includes enticing public space. But to varying degrees, each also shows the strain of inserting ample new growth into a constrained setting.

Leading the pack is Potrero 1010, with 453 apartments packed into a pair of structures, one of which looks like a lopsided metal egg floating alongside Interstate 280 near Mission Bay. Another, the 410-unit L Seven, fills a block with seven buildings at the Eighth Street off-ramp from I-80. One Henry Adams adds 239 apartments to Showplace Square and is the only member of the trio within a well-established district.

The stocky brick warehouses and wide-open feel of that area, long popular with homeware designers and showrooms, gave BAR Architects the design cues it needed to produce a complex that pairs strong but deferential architecture with a spacious mid-block plaza.

Two flat-topped buildings fill the block of Henry Adams between Division and Alameda streets, just south of the grassy roundabout that’s a district landmark. Each sticks to simple right angles, both in form and surface details.

There’s nothing adventurous here, though the lush vegetated walls on either side of the grandly scaled residential lobby add a contemporary touch. The broad bays are cloaked in stucco and black metal to convey a visual heft that echoes the century-old neighbors.

Back to Gallery Full-block housing developments meet challenge of staying... 5 1 of 5 Photo: Paul Chinn / The Chronicle 2 of 5 Photo: Paul Chinn / The Chronicle 2017 3 of 5 Photo: Paul Chinn, The Chronicle 4 of 5 Photo: Paul Chinn, The Chronicle 5 of 5 Photo: Paul Chinn, The Chronicle









This wasn’t an option at Potrero 1010, designed by David Baker Architects. The triangular block between Hubbell, 16th and Seventh streets for decades was part of a ramshackle landscape between Showplace Square, Potrero Hill and I-280. California College of the Arts was the only neighbor that might draw outsiders.

Now the area is booming, and Potrero 1010 fills a prominent site that called for something more adventurous than filling in the blanks.

Baker embraced the challenge.

The serrated metal egg, perched atop a glassy ground floor, wants to be a local icon. The much larger main building, a long blunt wedge, is skinned in everything from wood slats to six hues of stucco and bisected by a landscaped public walkway.

The other newcomer, L Seven, replaces a bus parking lot and fills the toughest site of all.

On the east is Eighth Street, a one-way grind with narrow sidewalks. Harrison Street on the south fills with cars heading away from I-80 as fast as they can. Directly across Gordon Alley is the Stud, a legendary gay bar and a reminder that this ragged stretch of South of Market came of age as a place where subcultures could flourish.

Instead of defining the corner of Harrison and Eighth with a marquee building to set the overall tone, architect Kava Massih takes a different approach to each of the seemingly independent structures (all of them share the same foundation). One forms a smooth glass cube. Another has a vivid grid of red metal, with wire mesh screening the recessed windows within.

Despite Massih’s design flair — including unexpected curves of translucent channel glass on the building’s base and cornice — the area’s 65-foot height limit wins out. The procession of one sidewalk-hugging box after the next feels relentless.

The interior of the block is more fun, with a publicly accessible lane ringing buildings from which large balconies pop out at jagged angles. But on a site zoned to hold more than 400 apartments, it would have been better to allow a mix of heights so that things wouldn’t feel so claustrophobic.

This was done at Potrero 1010: A narrow wing along Hubbell Street drops to just 20 feet, with glass walls pulled back from stark columns of board-formed concrete. The spaces hold design studios for California College of the Arts, an ideal counterpoint to the blue-collar firms across the way.

Other attempts to fit in are more elaborate.

Baker didn’t want to make the horizontal wedge seem too monolithic, so he juggled the rhythm of the bays and draped them in colors patterned on a sample of the skyline view from Potrero Hill.

“Conceptually this is camouflage,” according to Baker’s website. It’s also a case of trying too hard.

One Henry Adams has well-meaning missteps as well, with wide, purple brick walls that frame the lobby. This couldn’t have been cheap; still, the thin-skinned gesture is no match for the robust survivors to the east and south.

The difficulty with projects of this scale, and not just in San Francisco, is that the “lower is better” mantra is simplistic.

This doesn’t mean 40-story towers should pop up in all directions. But when a lid is slammed on large swaths of the landscape, yet there’s a call by politicians and planners for more housing, even the most nimble architect can do only so much.

Ultimately, the key is to break down large projects so that they tie into their surroundings at a pedestrian scale.

That’s certainly the case with Potrero 1010’s grassy and beguiling Daggett Park, which separates the egg from the wedge and was designed by CMG Landscape Architecture. It’s a space like none other nearby, complete with a dog park and a sculptural cascade of terraced seating.

The complex also welcomes the larger city with extensive high-ceilinged storefronts along 16th Street, which now serves as a gateway to Mission Bay.

“You have to think of projects like these as urban planning as much as architecture,” said Baker, one of the most prolific and inventive housing architects in the city. “That makes them interesting.”

At One Henry Adams, the public realm, by landscape architect Jeffrey Miller, unfolds with a delightful quirk: The spacious plaza and the outer walkway hover several feet above a new sidewalk.

The idea isn’t to keep out the riffraff — this block of Henry Adams Street was scooped low at some point to make it easier for workers to load and unload cargo. Rather than being ignored, the anomaly is celebrated.

As for L Seven, which is in the final stages of construction, the interior passageways hark back to South of Market’s original net of interconnected alleys. And Miller is redesigning Ringold Street with widened sidewalks coupled with art installations to celebrate another aspect of SoMa’s past: the blossoming of the gay leather culture in the 1960s and ’70s.

Each of these enclaves blurs the boundaries that once existed between where people work and where they live. To the extent that they also enrich the landscape, whether with open space or unexpected twists, they’ll leave a mark beyond what dense horizontal architecture can provide.

John King is The San Francisco Chronicle’s urban design critic. Email: jking@sfchronicle.com Twitter: @johnkingsfchron