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By Barbara Knecht

The difficulty of end-of-life disassembly of current buildings makes it obvious that better material choices need to be made in future buildings. Design for Disassembly experts add another voice to the growing chorus of architects who encourage the profession to take a leading role in determining the materials that will be used in buildings. Michael Stacey [see record, July 2004, page 153], Croxton, or Shell might choose different materials, but they would all be likely to agree that the selection and employment of materials must be specific to programmatic and construction requirements and closely tied to manufacturing processes.

Guy notes that we have had two significant and plaguing problems in 20th-century materials—asbestos and lead. Their toxicity has made building disassembly and materials reuse expensive, and sometimes impossible. Techniques for stripping lead paint from wood exist, but it can only be cost-effective if the wood has a high value architectural reuse: It is not cost-effective to strip wood for framing studs. Lack of standards for how to reuse some recovered materials is another barrier to achieving a closed-loop system. Wood grading and stamps have existed only since World War II, so structural integrity, moisture content, and species can only be surmised in materials pulled from older buildings.

Ultimately, it is what we build with now that will expedite future deconstruction. Some proponents would banish drywall, a composite of low-value materials that are completely destroyed in disassembly. Guy would argue that the closer a material is to its natural state, the higher its potential for reuse, and he advocates for simpler materials.

The entire industry will need to participate as we move toward zero-waste building construction. Perhaps in the future, architects will also produce deconstruction drawings and conduct deconstructability reviews. Materials will arrive at the site either ready to use, and therefore leaving either no waste or recyclable waste, or they will be packed in materials that can be returned to the product manufacturer for reuse or recycling. Building components will be labeled or bar-coded with disassembly instructions and constituent materials. Costs for demolition and deconstruction will plummet as waste disappears.