Jae’s career path was redirected by mid-life re-education (an MSc in Advanced Environmental & Energy Studies) and training as one of the first UK Certified Passivhaus Designers. That led to achieving one of the first three certified Passivhaus retrofit houses in the UK (a Passivhaus B&B), which won the Passivhaus Trust UK ‘Best Private House 2013’ award. Co-author of The Passivhaus Handbook, the first comprehensive book on Passivhaus (published 2012), Jae has most recently developed a timber frame based construction solution, the PH15 System, to reliably and cost effectively achieve Passivhaus. The PH15 System was shortlisted for the prestigious Ashden Awards, 2018.