PPIY were commissioned to design an energy efficient nursery extension at Bootham Junior School York that would not increase the School's existing energy usage. To achieve this we researched new technologies and construction methods and the extension was designed using PasivHaus energy conservation principles. The walls have three times the thickness of standard cavity wall insulation. Winner of a ‘York Design Award’ 2011 We were delighted that the project won a York Design Award in recognition of everyone's achievements.