Design for Disassembly

Naturally Wood

Salvaging timber for reuse is already showing promising signs that it is more than financially viable, representing a sizable boost to local economies.

“The economic incentive is becoming clear. With the old ’take-make-waste’ model, we’re leaving money on the table. We need to fix that, and therein lies the opportunity with a circular economy,” said George Patrick Richard Benson, Manager, Economic Transformation Decarbonization & the Just Transition at the Vancouver Economic Commission. 

2020 report, co-authored by the Vancouver Economic Commission, Unbuilders, and the British Columbia Institute of Technology, found that at current valuations, the estimated volume of salvageable wood in Metro Vancouver across the 780+ residential demolitions is worth approximately $340 million a year.

Beyond salvage, Design for Disassembly (DfD/A) in BC and Canada’s building sector is growing. While pick-up has been gradual, some examples are helping lay the groundwork for the broader industry. By definition, DfD/A is the design of buildings that anticipate future changes and dismantlement (in part or whole) for recovering systems, components, and materials. It means much of the building components can be reused as efficiently as possible at the end of their lifespan, avoiding demolition, diverting landfill waste, and reducing pressures on natural resources. Benson explained there is momentum for DfD/A and circular construction principles in the province and across Canada.

Built in 1996, the CK Choi Building at the University of British Columbia is an early example. It is recognized for extensive material salvage and reuse, in addition to applying principles of DfD/A. The project uses reusable components and a modular design throughout. Salvaged heavy timbers provided 60% of the primary wood structure. Over 50% of the building’s materials are examples of reuse or come from recycled sources. This includes steel, plywood, framing timber, and doors. 

The Wood Innovation and Design Centre, a more recent example, is designed with a deep focus on repeatable, reusable, prefabricated construction. It features wood floor slabs made of overlapping panels of 3- and 5-layer CLT joined together with adhesives and a mesh connector, reducing the amount of concrete needed and making much of the structure easier to disassemble and reuse. The vast majority of the building—including CLT panels and glulam timber columns and beams—can be dismantled at the end of its functional life, and the wood products can be used in a future structure. 

MEC, the BC-headquartered outdoor equipment retailer with long-standing eco-friendly roots, incorporated features into some of their stores’ design and construction that favour circular principles and, in some cases, future reuse and recycling. This includes exposed timber structural framing with bolted connections, and timber decks screwed down, making disassembly and reuse easier. And as a general rule, mass timber is a material well-suited to reuse, a material MEC has used in many of its stores across the country, including its Vancouver flagship store. Along with mass timber, the company has committed to minimizing the environmental impacts of all its retail outlets.

To fully realize a circular economy and timber’s potential contribution, experts point to the growing need to boost optimization across the entire industry, with each player in the supply chain working together with greater integration.

“Optimization tools like building information modelling (BIM), modular construction, the circular economy, and mass timber—all of these components are incredibly synergistic,” said Benson. Thinking of a building like a kit-of-parts can not only cut waste during onsite construction, it makes it easier for a building to be disassembled or adapted to new uses and enables an entire industry to collaborate more effectively, he adds. 

A growing number of BC-based projects, along with their design teams, are helping advance the optimization of mass timber construction. This includes just-in-time construction and digital technologies. 

BIM and Virtual Design and Construction (VDC), along with Digital Twins (DT), played a central role in designing one of the world’s tallest wood buildings, Brock Commons Tallwood House. From design modelling to construction modelling for onsite assembly, the design team leveraged the total capacity of these tools to test, troubleshoot, and ultimately streamline the entire construction process end-to-end. In addition to cutting waste and streamlining manufacturing, this innovative effort by BC’s building sector to assemble the tall wood tower as a kit-of-parts makes the building easier to deconstruct and repurpose at the end of its life. 

Shifting to a circular economy is not without its challenges. It requires significant coordination on the part of consumers and businesses, governments, and industry to change from a ‘take-make-waste’ approach to more circular, regenerative methods.

Made-in-BC timber products have an essential role to play, and momentum is mounting, according to Benson. Continued focus is needed on waste reduction; optimization; digital technologies; and design for durability, disassembly, and reuse. 

And for the province, the solution is at our back door. BC’s sustainably managed forests mean we can reduce our dependence on energy-intensive and non-renewable materials from afar while stimulating greener jobs here at home.

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