John D. Lesak

John D. Lesak is an Adjunct Assistant Professor in the Heritage Conservation program at the University of Southern California's School of Architecture. He is a Principal of Page & Turnbull, founding their Los Angeles office in 2006, and specializes in the intersection of sustainability and historic preservation. His work emphasizes environmental stewardship, socio-cultural impacts of environmental changes, and innovative approaches to preserving historic structures.

Lesak holds an M.Arch in Architecture & Structural Engineering from the University of Illinois Urbana-Champaign. He has led award-winning projects such as the seismic retrofit of the Capitol Records Tower and the adaptive reuse of the Riverside Public Library into The Cheech Marin Center for Chicano Art and Culture. His expertise includes heritage conservation, green building practices, and material science.

Active in professional organizations, Lesak served as Past President of the Western Chapter of the Association for Preservation Technology International (APTi) and as a mayoral appointee to the Los Angeles Mayor’s Design Advisory Panel. He co-founded APTi’s Sustainable Preservation Technical Committee and has lectured internationally on topics like seismic safety in historic structures and graffiti management in public buildings.

His research explores the socio-cultural dimensions of environmental sustainability and the ethical stewardship of historic environments. He teaches 557 Sustainable Conservation of the Historic Built Environment, bridging heritage conservation and green building strategies to address climate change and urban resilience.