PITTSBURGH (AP) Twenty-five hundred tons of concrete, 350 tons of steel and nine tons of aluminum window frames will be left after a seven-story downtown building is taken down.
But instead of ending up in the scrap heap, the concrete will be ground up and used to fill the site, the steel will be melted to create rebar and the aluminum will be melted and used in cans and other products.
Companies have become more environmentally aware, and that attitude is reflected in the buildings they work in –– and the ones they renovate or take down.
Officials at PNC Financial, for example, plan to recycle more than 70 percent of the downtown Pittsburgh building they began deconstructing Oct. 20, something that’s happening with increasing frequency at demolition sites all over the country.
"Traditionally, if someone was to demolish a building, they would simply go in with a wrecking ball," said Gary Saulson, PNC’s director of corporate real estate. He said PNC is being much more deliberate in how they take down the building, a process that will take about two months; the building is being replaced with a park.
The demolition of buildings in the United States produces about 124 million tons of debris every year, according to the Deconstruction Institute, a Florida-based group which encourages recycling of buildings and the use of recycled building materials.
Alan Traugott, a principal at Coraopolis-based CJL Engineering and a founding member of the U.S. Green Building Council, said the trend has been toward choosing deconstruction over demolition when possible.
"Rather than knocking it down and carting it off to a landfill, if you deconstruct a building and reuse its parts elsewhere, you’re saving labor, materials ... You are trying to avoid going for new virgin materials and all the embodied energy and associated environmental impact that reflects," Traugott said.
He said the practice has become more commonplace as a distribution network for used building materials has sprung up, citing as an example Construction Junction, a Pittsburgh-based nonprofit retail store for used and surplus building materials. The company saves 2,000 doors, 1,000 windows and 1,200 cabinets for reuse every year, according to its Web site.
Rebecca Flora, executive director of the Green Building Alliance, said about 90 percent of the construction waste generated from the building of the city’s David L. Lawrence Convention Center was recycled.
"Clearly as our land use becomes much more critical, doing this makes a lot of sense," Flora said.
According to the Minneapolis-based Institute for Local Self-Reliance, a nonprofit research and educational organization, some towns across the country have passed ordinances requiring recovery of construction and renovation debris. In Atherton, CA, 50 percent of waste from demolition projects must be recycled or diverted from landfills.
Peter Templeton, deputy director of the Leadership in Energy and Environmental Design project and International Programs for the Green Building Alliance, said different municipalities have different requirements. Some of the strongest programs are in place in Washington state and California.
"It’s basically looking at good resource management," Templeton said.
In Pittsburgh, PNC Financial Services bought the city’s former Public Safety Building in May 2004 for $4.2 million and immediately announced plans to take down the building and turn the space into a park. The company had previously built the world’s largest certified green corporate building at a site near the building, and they said deconstructing a building was a logical next step.
Officials estimate the building on the 1.5-acre site will yield 11,000 tons of waste, 8,000 of which is recyclable. In addition to the steel and concrete, 24 tons of exterior steel will be melted to be used in other products and the foam board ceiling tiles will be returned to the manufacturer to grind and make new ceiling tiles.
"Deconstruction is actually a process of going through the building and understanding what and how to capture the stuff," Traugott said.
Saulson said the process benefits businesses by creating and sustaining jobs at the plants where the building materials are sent. It also makes fiscal sense for PNC, he said.
"We’re going to save over $200,000 in dump fees alone," Saulson said.