In a pilot project conducted at Fort Leonard Wood, Mo., the Army found that deconstructing, rather than demolishing, three buildings allowed it to increase the percentage of material that could be diverted from a landfill.
In a standard demolition, a building is quickly torn down using mechanical equipment, with the primary goals being cost reduction and reducing the amount of materials sent to a landfill, reported the Army Corp of Engineers’ Engineering and Support Center, Huntsville. The Corps’ goal is to divert 60 percent of the materials following a demolition; the salvaged materials are either reuse or recycled.
During a deconstruction, a contractor removes the greatest amount of materials that are intact and suitable to reuse or recycle. Not all buildings are good candidates for deconstruction, however. Engineers must consider the type of construction, contents and condition and their suitability for reuse, as well as the project itself, project schedule, and markets and industry capabilities, according to the story.
The Fort Leonard Wood pilot involved three buildings — a chapel, laundry and warehouse. The contractor reused or recycled more than 250 tons of material from the chapel, for an 85 percent diversion rate; nearly 700 tons of material was reused or recycled from the laundry, for a 73 percent diversion rate.
During the contractor’s deconstruction of the warehouse, though, the building became unstable due to excessive rotting of the wooden structure. As a result, the deconstruction effort was stopped and the Army decided to demolish the building. Despite the snag, the contractor was able to reuse or recycle 297 tons of material, diverting more than 63 percent from a landfill.
Overall, the contractor reused or recycled 1,246 of the three buildings’ 1,717 tons of material, making the project a success, according to the Corps.
“Deconstruction is one of those valuable nuances in the demolition arena that may allow us to increase our diversion percentages without significant cost in time or dollars,” said Dave Shockley, chief of the Corps’ facilities division branch.