Rethinking Material Selection
Building Reuse is Just the Beginning
by Justin Koscher, President of the Polyisocyanurate Insulation Manufacturers Association
Building reuse is one of the building industry’s most impactful decarbonization strategies. Rather than demolishing existing structures and rebuilding from the ground up, design teams are instead opting to extend the life of commercial buildings through renovations, retrofits, and adaptive reuse projects. This approach lowers a retrofit project’s total emissions by avoiding the environmental impacts of more carbon-intensive structural materials such as concrete and steel that would otherwise be required in a new construction project.
Adopting this strategy makes for a compelling sustainability story. By retaining the embodied carbon already invested in a building, building reuse delivers environmental benefits long before the renovation is complete. This strategy may be particularly appealing to architects and designers working in Western states, where sustainability is often embedded in policy. For example, California became the first state to make embodied carbon targets a mandatory component of its green building standards code, also known as CALGreen. As of January 1, 2026, commercial projects over 50,000 sq.ft. are required to adhere to one of three pathways to reduce carbon emissions: building reuse, performance, and prescriptive requirements tied to product global warming potential.
California’s progressive green building policy reflects a broader recognition of the role existing buildings can play in reducing the environmental impacts of the built environment across the Western United States by preserving what is already in place, building reuse can reduce demolition waste, conserve natural resources, and maximize the value of existing building assets, making it one of today’s most effective ways to contribute to a lower-carbon built environment.
Transparent environmental data supports informed specifications
The concept of building reuse is powerful on its own, but the work doesn’t simply stop at preserving the existing structure. Every design decision made during a renovation, including material selection, also plays a role in the building’s long-term environmental performance.
Many large-scale renovation projects include upgrades to the building envelope to improve energy efficiency, reduce operational carbon emissions, and extend the building’s service life. These types of considerations can be especially important across the Western United States, where building reuse projects can be located in dramatically different climate conditions, from hot, dry environments in the Southwest to cold mountain climates and marine conditions up and down the Pacific Coast. In each case, building envelope improvements must be carefully evaluated within the context of the building’s location and performance goals.
As a result, design teams are increasingly evaluating building products not only for their expected performance, but also for their environmental impacts. That’s why for architects and designers working across the West, access to third-party verified, standardized environmental data is a must-have when it comes to proper specification.
One of the most reliable resources available today is an Environmental Product Declaration (EPD). An EPD is an internationally recognized document and standardized reporting tool that discloses the environmental impacts of building materials. EPDs are developed using product category rules that establish the frameworks and rules for conducting standardized life cycle assessments for specific product categories. These frameworks help to ensure that design teams can evaluate product options using consistent, objective data rather than relying on marketing claims.
To help support more informed material selection, the Polyisocyanurate Insulation Manufacturers Association (PIMA) recently published updated industry-average EPDs for polyisocyanurate (polyiso) products. These third-party verified and ISO-compliant declarations provide environmental impact data for polyiso roof insulation, polyiso wall insulation, and high-density polyiso roof cover boards manufactured by participating PIMA member companies in the United States and Canada.
The publication of PIMA’s updated EPDs represents a significant undertaking. Over a two-year period, data was collected, analyzed, and validated from participating manufacturing facilities across North America to create industry-average reports for polyiso products. For design teams working on building reuse projects, this report opens a window to comprehensive environmental impact information that reflects industry-wide manufacturing data.
For polyiso roof and wall insulation products, the EPDs include information on popular facer types, compressive strengths, and scaling factors. These types of details allow design teams to calculate the environmental impacts attributable to the specific polyiso product used in a retrofit project. Ultimately, having access to this industry-averaged environmental data empowers western design teams to make educated material selections and carefully consider the environmental impact of a building reuse project alongside its performance goals.
For many architects pursuing building reuse, the goal isn’t simply to preserve an existing building, but to make forward-thinking decisions about how that building will perform for years to come. Reusing an existing building preserves the environmental investment already made, while upgrading the building envelope with high-performance solutions like polyiso can reduce energy consumption throughout the remainder of the building’s service life. Polyiso EPDs can further support design decisions by giving project teams access to transparent environmental data as they evaluate material options.
For architects working on reuse projects across the Western United States, where progressive codes and varying climate conditions raise the bar for whole building performance, access to this product information can help design teams specify with more intention and confidence. Rather than viewing embodied carbon as a consideration that is separate from building performance, architects, and designers can evaluate both as part of a more comprehensive approach to building reuse.
In summary, by combining the environmental benefits of building reuse with EPD-informed material selection, western architects and designers can extend the service life of existing buildings, improve their performance, and contribute to a lower-carbon built environment. Architectural West readers can view and download PIMA’s EPDs for polyiso roof insulation, polyiso wall insulation, and HD polyiso roof cover boards at https://www.polyiso.org/page/EPDs.
