Nod to History would craft best S.F. architecture

The buildings lining the lone block of Sumner Street in San Francisco's South of Market district will never be mistaken for the Painted Ladies of Alamo Square.

The entrance off Howard Street is flanked by two-story warehouses from the 1920s, one concrete and one brick. The alley itself displays small buildings of various styles, including a one-story wooden home from 1906 with columns framing the door and a huge bay window.

Yet 11 buildings on the block, and 467 more on the blocks around it, are deemed "contributors" to what could become the city's largest historic district - a collection with few obvious landmarks that instead offers clues to the blue-collar city of the past.

This and similar landscapes deserve such attention; for too long they were taken for granted. The double-edged sword is that new layers of protections could undermine the varied architectural character that makes such areas distinct.

In the case of the proposed Western SoMa Light Industrial and Residential Historic District, that character is easy to miss.

Bounded very roughly by Seventh and 12th streets on the east and west, Harrison Street on the south and Minna Street on the north, it's an area most people drive though. The main drags of Howard and Folsom streets are a procession of masonry boxes filled by auto repair shops and retail showrooms, agencies and offices, restaurants and bars and housing at all price levels.

Documenting the detail

It's on foot that you begin to understand why the city hired the architectural firm Page & Turnbull to document the blocks as part of a larger SoMa survey. Warehouses sport art deco frills. On the alleyways you might find a faded apartments next to a former dairy.

"What's interesting about the district to me, besides the scale, is the casual mix of industrial and residential," said city planning director John Rahaim.

The proposed district defines the "period of significance" as 1906 to 1936, from the destruction of the earthquake to the creation of the Bay Bridge. Contributing buildings must date from that era and retain their design integrity - no matter how humble the design.

The potential district and four smaller ones within the SoMa survey area will be reviewed by the city's Historic Preservation Commission on Dec. 1. The final decision on whether the districts should become official rests with the Board of Supervisors.

Even if this occurs, contributing buildings can still be replaced by new construction. But findings of historic significance create an expectation that future development in the area should be "compatible" with what came before - as subjective an architectural term as there is.

In Western SoMa, the post-1936 buildings are a key part of the neighborhood's story, especially ones since 1970 that might not have been allowed elsewhere in the city. It's a variation of the cultural tolerance that allowed the defiantly sexual Folsom Street Fair to take root.

You see this on Sumner Street, where the mix includes four townhouses from 1991 designed by Donald MacDonald. They're clad in shiny metal, each sporting a bay window that looks more like a pagoda than a Victorian affectation.

Out of context? Not at all. The quartet is a snapshot of an era, surprising but thoroughly at home.

Inevitably, some building owners are nervous about extra attention from city planners.

E-mail John King at jking@sfchronicle.com.

This article appeared on page C - 1 of the San Francisco Chronicle