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Lisa Heschong

Lisa Heschong is a Fellow of the Illuminating Engineering Society. She was a licensed architect for 30 years and a principal of the Heschong Mahone Group (HMG), an energy consulting firm based in California, from which she is now retired. At HMG she led numerous field studies of lighting use, including those that found a correlation between more daylight and better student performance, and which helped to establish the outdoor lighting codes in California. She also led the team that developed the annualized daylight performance metrics, spatial Daylight Autonomy (sDA) and Annual Sunlight Exposure (ASE), as defined in IES/ANSI LM-83.

Heschong is the author of Thermal Delight in Architecture, (MIT Press 1979) and Visual Delight in Architecture: Daylight, Vision and View (Routledge, 2021), along with numerious technical publications. She speaks internationally on the importance of light for health, and access to both natural daylight during the day and natural darkness at night.

Heschong has a Masters of Architecture from MIT, where she was awarded the AIA School Medal. She has since received three life-time achievement awards, including most recently the IES Medal in 2023.