The brash apartment building at Sixth and Howard streets is designed to reflect its surroundings, with bold touches that include a deep nine-story masonry facade.

But the most site-specific flourish is easy to miss: the taut, thin wires strung above the top of each balcony railing, part of the quest to make the new Bill Sorro Community pigeon-proof.

“The thing is to keep them from getting a foothold,” said Owen Kennerly, whose Kennerly Architecture designed the 66-unit building for nonprofit developer Mercy Housing California. “If you know there’s going to be a major issue, the best solution is to prepare for it in advance.”

Though pigeons are a problem throughout San Francisco, the challenge at Sixth and Howard is daunting because of what stood there before, a long-empty residential hotel that became a coop of Brobdingnagian proportions.

The structure was the Hugo Hotel, gutted by fire in the 1980s and finally demolished by the city in 2014. In the interim, it was best-known for “Defenestration,” an eye-popping art installation of salvaged furniture that seemed to be spilling from windows or, in the case of a quartet of long-legged piano benches, dancing off the roof.

Artist Brian Goggin installed “Defenestration” as a temporary blast of guerrilla art in 1997, but it gained such a following that it stayed in place even after the city used eminent domain to purchase the blighted corner building in 2009. When the site was cleared to make way for Mercy Housing’s project, “Defenestration” was dismantled once and for all.

Back to Gallery New SF building uses wiring, ‘shock’ tape to deter... 5 1 of 5 Photo: Santiago Mejia, The Chronicle 2 of 5 Photo: Santiago Mejia, The Chronicle 3 of 5 Photo: PAUL CHINN, SFC 4 of 5 Photo: PAUL CHINN, SFC 5 of 5 Photo: Lacy Atkins, The Chronicle









Construction began in 2015. As the concrete started rising, the displaced pigeons did their best to return.

“When you have a major construction project and they’re still trying to touch down, you know you’ve got a problem,” said Barbara Gualco, director of real estate development for Mercy Housing California. “This was roosting central for many years.”

Think about it: a four-story shell on skid row. Windows, some broken, with brick sills ideal for basking in the sun. Even “Defenestration” added to the appeal — if humans can lounge on furniture, why not the birds disdained by legendary Chronicle columnist Herb Caen as “rats with wings”? As the years passed, generations of pigeons were programmed to think of Sixth and Howard as their home.

During construction, workers from general contractor James E. Roberts-Obayashi Corp. hung compact discs from their scaffolds to keep the birds at bay. Meanwhile, Kennerly’s firm and Mercy worked with a subcontractor who specializes in pest management.

Rather than go for the unsightly obvious — brush-like spikes — Bill Sorro Community was designed with two specific responses.

One is the use of wire on the railings, high enough to slip a hand beneath it but low enough to (theoretically) keep pigeons from gaining a toehold, or whatever it is that pigeons seek. The other is “shock wire,” inch-wide tape that is applied to window sills and is connected to electric wires hidden from sight.

“It’s a low current — they don’t get electrocuted or anything,” Kennerly assured this reporter. “Just enough to make them uncomfortable.”

The building will include 52 apartments for low-income housing and 14 apartments for developmentally disabled adults. Residents are moving in while workers complete the exterior and lobby.

So far, the proactive remedies seem to be doing their job.

Which, viewed in a different light, means hundreds or even thousands of pigeons have been displaced. They can’t go home again.

“That instinct to return to the roost is quaint in some ways — except that it becomes such a problem,” Gualco said. “They’re survivors. You’ve got to hand it to them.”

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