In the ongoing effort to maximize the use of materials in the built environment and minimize carbon impacts, the movement toward designing buildings for eventual reuse of parts and materials is gaining new impetus with advancements in technology and industry innovation.
At Forell Elsesser, we are adding Deconstruction Drawings to our plans to show the project sponsor, architects, builders, and future interested parties how our buildings can come apart to reuse components. Buildings inherently should not come apart, but only through design and proper planning can the reuse be possible.
This trend for building reuse and reducing waste isn’t entirely new, and individual cities and other jurisdictions are even mandating such considerations. But the commercial real estate industry also needs to take a greater leadership role in envisioning such processes and making it easier to put into effect.
The City of San Francisco is eyeing the reduction of construction waste through improved processes in both advanced design and demolition or deconstruction. It already has a zero waste target for construction and a current ordinance to reduce debris sent to landfill or incineration by 50 percent by 2030.
Another Bay Area city, Palo Alto, already requires that project sponsors pursue reuse and deconstruction strategies driven by the landfill-diverted waste exceeding 40 percent from the construction industry alone. Its 2018 regulation, which is driving some of the most pro-active deconstruction in the country, is aptly subtitled, “Effective July 1, 2020, demolition will no longer be allowed.”
Clearly, if such efforts in the U.S. and worldwide are to be successful, we in the design and construction industries must do our part. Designing our buildings for parts-reuse is a better step towards a future where construction components have an equal or greater value even after their first use.
Most designers and engineers have a story about playing with building blocks as kids and how it helped shape their interest in building and creating things. This statement is true for me, but I also learned some lessons later in life.
Walking through a store recently reminded me of how different these building-block toy and entertainment offerings are compared to when I was a kid. The things you can create now out of the box can be amazingly detailed and intriguing.
Today, you can buy the Eiffel Tower, a Bonsai tree, the Concorde passenger jet, or even Hogwarts. There is something special about constructing piece by piece to see something come together. If you have kids, inevitably, you’ve experienced heartbreak as the masterpiece is deconstructed and reassembled, sometimes devolving into a Frankenstein monster as all that hard work and time investment is gone. However, the second or third life can be quite interesting as creativity sets in to evolve into something yet again, such as a Star Wars spacecraft mixed with the Batmobile, for example.
The incredible thing about this transformation is that there’s no change to the components’ form and function when reused.
When can we build actual buildings that way?
In current commercial real estate practice, demolition of buildings creates a significant portion of construction waste, with little material able to be reused. Additionally, even more energy and materials are needed to replace an old building with a new one, no matter how sustainable or “green” the design is. Construction today has many single-use parts that have one function and one use.
At best, some portions of building parts can be recycled, like structural steel components or lumber that can be repurposed in new buildings or concrete rubble from tearing down a structure that is put to use as base rock or construction fill.
For the most part however, demolished construction is essentially waste.
Changing construction debris back into valuable materials can be energy-intensive, too. This type of recycling is considered a downcycle. Building blocks that kids use are a perfect example of materials that have no downcycle, or upcycle, for that matter, because they can be reused indefinitely.
This interchangeability is an ideal goal, though I’m not suggesting building components can be as flexible to reuse as LEGOs. While they are the poster-child example of zero downcycle, a creative demonstration in the U.K. using 3 million of the little bricks has proven to be a building that nobody wants.
- A new approach from inception
But we are making progress in rethinking design and construction for reuse on the larger scale.
A key, initial step for improving building design is to consider our material choices and how we design buildings to go together and come apart, that is, designing for deconstruction.
Chemical adhesives, embedded parts, weldments, and binders connect building components but are not designed to come apart—by intent of design. Creating a deconstruction potential for a component requires a mind shift. Good design is bringing pieces together as well as being able to remove and separate them when the time comes for reuse. Further, the parts should be configured so that reuse is possible as a building block for future construction, enabling a higher reuse potential and economic value.
That’s why our firm and others are beginning to add Deconstruction Drawings to our plans that show a builder or an eventual de-constructor how buildings can come apart for reuse of components. Essentially a bill of materials with essential material data will allow future material “scavengers” and entrepreneurs an insight into how the building materials can be upcycled.
Some day, we envision project sponsors, architects, contractors, cities, and everyone involved in a building’s life cycle will hold a more commonplace view of construction components having an equal or greater value after the first use.
For that, I for one would owe a great big thank you to my childhood LEGOs.
Author: Geoff Bomba, Principal & Director of Engineering Operations at Forell Elsesser Structural Engineers.
