The U.S. Army Engineering and Support Center, Huntsville Facilities Reduction Program (FRP), in coordination with the Kansas City District, recently finalized a deconstruction pilot project at Fort Leonard Wood, Missouri.
The project, awarded in September 2014, cost less than $800,000, $10.31 per square feet, and entailed the salvage and reuse of materials from three World War II-era buildings.
During straight demolition a building is quickly and efficiently torn down, usually with large mechanical devices like excavators, with the main goals being cost reduction and material diversion.
“We reduce real property footprint at minimal cost and divert as much of the material from the removed building as possible to other financially viable uses – reuse or recycling – in lieu of sending it all to a landfill,” said Dave Shockley, Facilities Division branch chief. “The FRP is meeting or exceeding the 60 percent diversion standard using the demolition approach.”
However, FRP is always exploring better ways and means of getting the job done, Shockley said.
“Experience is a great teacher,” he said. “We realize there are situations where the way we’ve always done it may have been good enough, but we are not willing to just rest on past success when we have the ability to learn more and make it better.
“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,” Shockley said.
Engineer Construction Bulletin (ECB) 2015-19, states “deconstructing buildings and structures to recover materials can significantly reduce demolition waste.” The ECB also says project personnel have to be realistic when assessing a building for deconstruction because they can’t all be deconstructed within the Army’s cost and schedule parameters.
When deconstructing a building, a contractor removes the greatest amount of materials, components and products that are intact and suitable for reuse or recycle.
When material is reused, it is used for its intended purpose. For example, a door or window would be used as a door or a window.
However, when an item is recycled, it can be broken down and used for something else. While recycling diverts material from landfill, it still requires energy to be transported and processed, and if it can’t be recycled then it incurs disposal costs.
The Fort Leonard Wood buildings provided a situation for deconstruction that also supported the Installation Strategic Sustainability Plan for Fort Leonard Wood, said Bryan Parker, Directorate of Public Works (DPW) chief of planning.
In 2010, Parker went to Joint Base Lewis-McChord (JBLM), Washington, as the Fort Leonard Wood DPW master planner to discuss sustainability and find new ways for Fort Leonard Wood to accomplish its mission without wasting water, land or fuel.
“Some of the people I had talked to were in the solid waste arena and they were talking about how they had just completed a project where they had deconstructed some old wood barracks and recovered the timber,” Parker said.
Parker used JBLM’s deconstruction method as a baseline for the World War II-era buildings project – a laundry, warehouse and chapel.
First, the buildings had to be evaluated.
When evaluating a building for deconstruction, 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.
Driving this process is exactly what former Research Architect Tom Napier, Construction Engineering Research Laboratory, did with the Fort Leonard Wood buildings.
“My role was to help support Fort Leonard Wood with the expectation that this project would be completed in parallel with the other sustainability demonstrations, and we would have a result and conclusion for the material salvage and reuse along with water quality and energy,” Napier said.
Several things Napier looked at included the nature of the materials, which were mainly dimensional lumber, and whether there was a market, which there was, he said.
Because there was a market for the lumber, deconstruction became even more feasible and work on the project began.
But, after the project was underway, it hit a snag; the warehouse became unstable during deconstruction efforts because of excessive rotting of the wooden structure. Due to the increase in risk to contractor employees working inside and around the building, the decision was made to stop deconstruction and demolish the building.
However, while the building survived only a portion of the deconstruction effort, not all was lost. Bhate, the contractor, was still able to reuse or recycle 297 tons of material, diverting more than 63 percent from landfill.
The two buildings left – the chapel and laundry – proved even more successful. From the chapel, more than 250 tons of material was reused or recycled with almost 85 percent diversion, and nearly 700 tons of material was reused or recycled from the laundry with a 73 percent diversion rate.
Overall, the three buildings totaled 1,717 tons of material of which 1,246 tons was reused or recycled, making the project a successful venture.