To celebrate Earth Day 2023, we are going to share our ongoing research on deconstruction and reuse that is increasingly relevant in the AEC industry. Today we will start with what and why.
The construction industry consumes a lot of resources and produces a tremendous amount of greenhouse gas emissions in every life cycle stage, with the majority occurring during the product manufacturing and construction phases. The chart below shows how much buildings account for various aspects globally according to research by Dr. Gaetano Bertino and his team.
This statistic is facilitated by the linear economic model currently used by the construction industry, where new materials for construction are extracted and disposed of at the end of life. Now enters the circular economy approach, where deconstruction is employed, rather than demolishing building elements and sending to a landfill.
Deconstruction is the process of carefully dismantling building components and structures so they can be either reused or recycled. There are two types of deconstruction:
- Soft Strip – removing all the nonstructural elements of a building from both inside and outside to facilitate refurbishment, renovation or demolition. This process is typically shorter and can anywhere from a few days to a few weeks.
- Full Deconstruction – all building components including the structure are taken apart to be salvaged. This process is longer and can span from a couple of weeks to months.
According to a report by the Delta Institute, 70% of the materials can be recycled and up to 25% can be reused from a typical home deconstruction, diverting up to 75-90% of demolition waste from landfills.
For commercial typology, one can look at the Fort Carson Old Hospital Complex, built during World War II, as an example of how materials including cinder blocks, cement, steel, wood and fixtures can be recovered and recycled up to 93% with deconstruction.
By upcycling the materials, we can gain many socio-economic and environmental benefits:
- Minimize pollution and global warming potential associated with manufacturing and construction with new materials.
- Increase the availability of lower-impact reusable materials in the marketplace.
- Support local economies and create green jobs.
- Gain financial incentive through sales or tax benefit (donation) at the end of the building’s service life.
- Avoid the tipping fees associated with sending materials to landfills.
With new constructions constantly being executed on sites with existing buildings, it is worth re-evaluating our urge to clear sites and have a blank slate for design. What if elements can be salvaged? Stay tuned for the following post on why and how!