An interview with leading architectural educator Blaine Brownell, FAIA, on the latest in sustainable-materials research—and on where it’s headed next

Interview by Sheri Hansen

The materials category in the 21st Century Development matrix points the way to a future where all building materials are regenerative and have no negative impact on human and ecosystem health. Transparency and consistent articulation of principles that support the production and use of nontoxic, ecologically restorative, and socially equitable materials are essential in moving toward this goal. Evaluating Red List status (a compilation of harmful-to-humans chemicals and materials assembled by the International Living Future Institute), embodied carbon footprint, and net-positive waste can help designers improve in this category.

Blaine Brownell, FAIA, the interim head of the School of Architecture in the University of Minnesota College of Design, was recently named the director of the School of Architecture at the University of North Carolina–Charlotte. His research focuses on emerging and sustainable materials, and he has authored several books and many articles on the future of materials in architecture.

What have you been teaching in relation to materials at the University of Minnesota College of Design?

I’m teaching a course called Material Performance in Sustainable Building, which is a graduate seminar focused on environmental considerations in material selection and application. The class is one of four foundational courses required for all Master of Science in Sustainable Design students and was jointly developed by several School of Architecture faculty members and research fellows in our Center for Sustainable Building Research.

I also teach an undergraduate lecture course entitled Material Transformations: Technology and Change in the Built Environment. I call this the missing counterpart to Materials and Methods, which is a standard course in preprofessional architectural curricula. The typical Materials and Methods course aims to educate students about the best current practices in material applications. My class reveals how such practices change over time and investigates the nature of disruptive innovation as well as the broader social and environmental effects related to material applications in architecture.

Are students seeking more information about sustainable materials and systems?

Absolutely. Many students aspire to develop knowledge in this area, and our sustainable materials courses are quite popular. Given present concerns about climate change, many students feel a personal commitment to this topic. Additionally, students recognize the fact that architecture firms are increasingly seeking future employees with this expertise.

What trends are you seeing in materials education related to sustainability? How does that match up against the 21CD assessment criteria (Material Plan, Embodied Energy and Carbon, and Waste)?

A primary focus of sustainable materials education has been the identification and avoidance of Red List chemicals. Milestone publications like Rachel Carson’s Silent Spring and William McDonough and Michael Braungart’s Cradle to Cradle have brought significant attention to the detrimental effects these substances can have on human and environmental health. This focus aligns well with the Material Plan criterion of the 21CD model, in which no Red List ingredients are allowed in the Living Community Principles standard. Waste is also a prominent topic, which is addressed in the Waste assessment criterion.

Embodied energy and carbon are currently attracting increased attention in sustainable materials education. The embodied energy of materials accounts for a significant portion of the first 15 to 20 years’ worth of energy consumption in new buildings. As we become more efficient in the use of operational energy, a more significant part of buildings’ energy consumption will effectively be embodied in its materials. The 21CD assessment criterion of Embodied Energy and Carbon addresses this reality, and its Living Community Principles standard requires the complete offsetting of embodied carbon in buildings.

How can students employ the material levels in the 21CD matrix in their work as professionals?

Students and architects should review the 21CD model goals with their clients so they can discuss shared values and identify goals that are both aspirational and realistic. A critical aspect of meeting the 21CD criteria involves material accounting, so students should become familiar with the Living Community Challenge standards of tracking material metrics in a project. The International Living Future Institute platform on which 21CD is based is well established in the field, so students who apply its methods will also be adhering to 21CD guidelines.

Where is the design community headed next when it comes to materials? Where will the next generation of architects take us?

We have much work to do. Building construction, use, and demolition remain incredibly wasteful and ecologically detrimental, despite all of our progress. Developing a clear sense of material impacts is challenging because materials have not been characterized for their environmental properties as much as they have been for their engineering properties. So, we need more and better material data to make informed decisions.

Another critical step concerns establishing synergistic goals between different environmental assessment criteria. For example, we need a total net-zero framework that includes both energy and materials, because they are interrelated concerns. Similarly, different disciplines like architecture, civil engineering, and urban planning need to coordinate more closely regarding shared environmental targets. Compartmentalization is a convenient approach to conducting environmental assessments, but the future is about mastering holistic, integrated systems.

21st Century Development (21CD) is a new framework for achieving the best in development through radical incrementalism. How can we make strides in key areas of building performance to provide a healthy environment for all people and living systems today and into the future? How can we move, step by step, toward a regenerative reality in architecture? This robust tool for architects, developers, funders, and policy makers provides detailed yet easy-to-digest answers.
Learn more about the 21st Century Development performance areas, development matrix, and case studies at