Kat Klingenberg, founder of passive building non-profit Phius, discusses the explosive growth in passive building interest. From building the first certified passive house in Champaign, Illinois, to working on 53-story towers in Brooklyn, she explains how the movement has evolved beyond energy efficiency. Secondary benefits like air quality and grid-resilience are now the primary selling points, "energy savings is just gravy," she says. Klingenberg addresses common misconceptions, shares practical advice for getting started, and delivers a clear message: "It's time to retool."