Adam Dadeby and Janet Cotterell are directors of Passivhaus Homes Ltd., which has recently completed one of the very few fully Certified Passivhaus retrofits in the UK - featured in their book The Passivhaus Handbook, due out in 2012. The retrofit is also exceptional in having achieved one of the best air-tightness results in the UK. More information on Passivhaus and on Adam and Janet can be found at www.passivhaushomes.co.uk. Janet is a chartered architect with over 20 years' experience. She is also a Certified Passivhaus Designer and holds an MSc in Architecture: Advanced Environmental & Energy Studies. Janet has a history of working in sensitive settings (conservation areas, listed buildings, historic parks) and therefore is familiar with the use of traditional and natural materials. In more recent years a growing appreciation of the importance of sustainable building practice (and a growing dissatisfaction with mainstream building practice and culture) has lead to a process of re-education and re-evaluation, culminating in a new focus on the implementation of low-energy design principles and in more collaborative teamworking. Adam was previously employed in the NHS, then, in Berlin, in foreign language training and, back in the UK, in information technology. He is a Certified Passivhaus Consultant and member of the AECB (the Sustainable Building Association) and holds a postgraduate diploma in Architecture: Advanced Environmental & Energy Studies from the Centre for Alternative Technology (CAT). Studying at CAT has been a great opportunity for Adam to consider different approaches to 'sustainability' and 'resilience' as they affect building practice.