Preserving buildings is greener than building them

BERKELEY, Calif. — Americans love tearing down buildings. We rip up our homes to the studs, scrape them down to their foundations and are riveted by the ultimate demolitions: imploding skyscrapers. It's all part of a cultural need to make way for the new and improved.

But the construction and operation of buildings send up twice as much greenhouse gas emissions as the entire U.S. transportation sector, according to the National Trust for Historic Preservation. (Analysts with the federal Energy Information Administration say it is probably closer to even, all factors considered.)

In this, preservationists have found a new calling for their old cause. They are preaching against the evils of teardowns — not to save the past, but the future.

"It makes no sense for us to recycle newsprint and bottles and aluminum cans while we're throwing away entire buildings or even entire neighborhoods," says Richard Moe, president of the National Trust for Historic Preservation.

Moe has become a leading evangelizer of this niche-market green gospel. He spoke on a recent evening from the pulpit at the First Church of Christ, Scientist, a national historic landmark on the fringe of the University of California, Berkeley campus. The Gothic-influenced church, with its interior concrete supporting columns and muscular timber roof supports, is considered the masterwork of prominent Bay Area architect Bernard Maybeck.

Moe's message: "Preservation is sustainability."

And while the speaking tour is new, he likes to point out that the national trust has been talking about the issue for some 30 years. In 1980, after a round of oil price shocks, the group printed a poster depicting an old building in the shape of a gas can.

Which brings Moe to his present-day argument. "Buildings," he says, "are vast repositories of energy."

"It takes energy to manufacture and to extract building materials, more energy to transport them to a construction site, still more energy to assemble them into a building," he says. "All of that energy is embodied in the finished structure — and if the structure is demolished and landfilled, the energy locked up in it is totally wasted."

A typical 50,000-square-foot commercial building "embodies" the equivalent of 640,000 gallons of gasoline, according to the Advisory Council on Historic Preservation, which advises the White House and Congress on historic preservation policy.

The very process of demolishing uses more energy and creates tons of waste. And of course, the construction of a new building expends still more energy, in hauling materials, lighting the structure and running tools. Building a new 50,000-square-foot office structure releases the same amount of carbon into the atmosphere as driving a car 2.8 million miles, Moe says.

Moe goes out of his way to counter the argument that energy-efficient new buildings quickly offset the energy used to tear down and replace an older building. Even if 40 percent of materials in a new building are recycled, it takes about 65 years for a "green, energy-efficient new office building to recover the energy lost in demolishing an existing building," he says, citing research by the Illinois Historic Preservation Agency.

It won't work everywhere, Moe acknowledges.

Seattle, for instance, is encouraging higher population density in its urban center. Replacing small, old structures with tall, new ones will require teardowns, says Paul Mackie, an area manager with the Western Red Cedar Lumber Association.

Not surprisingly, the lumber group, too, has gotten in on the climate change act. Timber products, Mackie says, are "cleaning machines" that suck carbon out of the air and are renewable; processing them emits a fraction of the carbon as steel manufacturing, he says.

"Our position is that we need both renovation and new construction," Mackie says. "Using sustainable building materials like wood — especially western red cedar — that have the best environmental values are great choices."

Moe recognizes he is asking Americans to resist a deeply embedded impulse.

Tearing down and rebuilding are "part of the American ethic, it's part of American culture, but it is changing, thank goodness," he says in an interview at the church. "There's such a mindset in this country that a building has a life cycle and if you live out that life cycle, tear it down instead of trying to retrofit it for increased energy purposes."

"We're dealing with attitudes that have been set for many, many years, for generations," he said. "That's been the biggest impediment to preservation in America for a long time, is that people tend to think new is better than old, tear out the old, build the new. But we're changing that."