GREEN CITY It’s hard to argue with Craig Nikitas when he says, "The greenest building is the one that exists now."
As a senior planner with the San Francisco Planning Department, Nikitas knows that a ton of energy is wasted tearing down the old and erecting the new. Energy embedded in the original materials and construction which often last a century or longer is also destroyed. And it all ends up in the dump, replaced by new products that might, if you’re lucky, hold up for a fraction of the lifetime of the old components.
Michael Tornabene is a designer at Page and Turnbull, Inc., a Nob Hill District architecture firm specializing in preserving historic buildings, notably the asbestos-laden Old Mint and the Ferry Building. He said the Bay Area is distinguished by its thousands of gorgeous Victorian, Edwardian, and Craftsman homes, as well as its green sentiment. Restoring old buildings can be tricky because their features aren’t standardized. Even so, their age can also be their best virtue.
"What’s great about sustainable upgrades to an historic home is most of the historic homes we’re dealing with were constructed before a mechanically integrated system was developed," Tornabene said, noting most pre-1950s structures already had nice green features such as passive solar orientation, designed into them rather than being built around unsustainable elements think air conditioning that are harder to green.
Where to start? First, pick off what Tom Dufurrena, a principal at Page and Turnbull, calls "all the low-hanging fruit the easy things that have the least cost and the most benefit." Weather-stripping the doors and those rattling old windows, insuutf8g the attic (40 percent of heat is lost through the roof, he said), and replacing old, inefficient appliances with Energy Star models are the three simplest and best historic home improvements. All are noninvasive and energy conscious, and they don’t require a permit from the city.
Such suggestions were just the beginning of measures photographer Peter Bruce took to make his family’s 117-year-old Upper Haight Victorian more efficient and comfortable. Over a five year period, they knocked their monthly electric bill from $250 to $160 by replacing their refrigerator, installing a dishwasher that recycles heated water, and putting in nearly 100 percent efficient hot water heaters.
But Bruce didn’t ignore the low-tech, remembering to string a clothesline and using curtains as more than mere decoration. "Dark, heavy curtains make a world of difference," he said, explaining that they hung these over north- and east-facing windows to keep the rooms toasty. He put sheer, light-colored curtains over west windows to allow in afternoon warmth.
Curtains or no, windows are the controversial linchpin in any discussion of building preservation and sustainability. "There’s almost the knee-jerk reaction from a sustainability point of view to replace your windows with double-paned windows," Dufurrena said. "On an historic building, if the windows are a historic feature which they almost inevitably will be then there’s an issue right there with compromising the integrity of the building."
Old window frames are made from higher-quality materials in San Franciscan Victorians this often means rare first-growth redwood than most modern energy-efficient alternatives. The National Trust for Historic Preservation cites studies showing it could take a century or longer for a replacement window, typically made of toxic vinyl, energy-intensive aluminum, or a wood composite, to pay for itself in energy savings.
"The worst thing you can do is take out old wood windows and throw them away and replace them with vinyl," Nikitas said.
He said that when Sup. Aaron Peskin was working on the Green Building Ordinance last year, the big question was how to create incentives encouraging people to reuse historic buildings. They devised a system awarding points toward their mandated green building requirement for retaining historic features, and keeping the windows represents a big chunk of the points.
"It’s about the truth of the building and the preservation ethos," said Cara Bertron, Page and Turnbull’s cultural resources specialist. "Those are really hard things to articulate to people who may see the energy savings as worth it."