THE OPTIMIZATION OF BUILDING DECONSTRUCTION FOR DEPARTMENT OF DEFENSE FACILITIES: FT. MCCLELLAN DECONSTRUCTION PROJECT

Abstract

Deconstruction is the selective dismantling of building structures to recover the maximum amount of primarily reusable and secondarily recyclable materials in a safe and cost-effective manner. Deconstruction is a labor intensive process and can be difficult to achieve in a time-efficient and economical manner for light wood-framed buildings. Deconstruction techniques that balance hand and mechanical labor must be developed to maintain the integrity of materials for reuse and obtain maximum salvage value per unit of cost and time-on-site. This project entailed the removal of three identical WWII-era two-story wood-framed barracks buildings at Ft. McClellan Army Base, Anniston, AL, using hand de-construction, combined mechanical and hand deconstruction techniques, and a traditional demolition method, i.e., mechanical reduction and disposal, in order to determine “optimal” deconstruction techniques based on salvage value per unit of cost. The maximum practical materials salvage from the study buildings using 100% hand deconstruction techniques was 39% of the mass by weight. A combination of hand and mechanical techniques was discovered to have approximately the same economic efficiency as 100% hand deconstruction, measured as a ratio of gross cost per salvage value, with a 44.6% reduction in total labor-hours, and a reduction of only 7% of salvage materials by weight. These findings indicate the potential for greatly increasing wood-framed building deconstruction practice relative to the additional time-on-site and labor that is required, compared to demolition, while optimizing economic benefits. This paper describes the research methods and deconstruction techniques employed, and lessons learned to advance the practice of deconstruction to be more economically competitive and time-efficient.