The death of 206 College Avenue was slow and painstaking. Over several days in January 2022, dozens of bundled-up volunteers swarmed over the three-story property, a tired wooden boarding house built in the early 1900s in Ithaca, New York. Long used as rental apartments for Cornell University students, the 13-bedroom house was set to be demolished, along with several neighboring structures of the same vintage, to make room for a new multi-use complex. But while those buildings were quickly reduced to rubble by trackhoes, the house at 206 was deconstructed, piece by piece, so that its elements could be used again.

The Catherine Commons Deconstruction Project, an effort by Cornell’s Circular Construction Lab, was a large-scale pilot designed to show how building waste can be kept out of landfills. As volunteers pulled nails out of fir, oak, and walnut boards and hauled lumber off to be sorted and redistributed, a team of eight workers with heavy machinery began meticulously sawing, slicing and removing 8-by-18-foot panels of the old building. These were trucked off to a warehouse, where they’d be taken apart and recycled.

The labor that went into this process was substantially more than a typical demolition. But it avoided the societal penalties left behind at nearly every building and demo site across the US. The sheer volume of waste generated by knocking down, adding to or renovating buildings in the US is stunning: 600 million tons of construction demolition waste annually, according to the most recent EPA estimate from 2018. Roughly 75% gets ground up into aggregate and fill, and only a small share is recycled and reused, necessitating production of new material for the next project. For scale, municipal solid waste only accounts for 300 million tons every year.