Delta Q (formerly Piers Sadler Consulting) is a specialist Passivhaus consultancy operating across England and Wales. We are certified Passivhaus designers and consultants working mainly for contractors and public sector clients on Design and Build Passivhaus developments through RIBA Stages 0-7. Projects include numerous schools, mid- and high-rise apartment blocks, low-rise housing developments and individual houses including a range of refurbishments, and perhaps the UK’s first EnerPHit of a modern insulated building. Success requires more than just an understanding of technical issues. Our collaborative approach combines specific project and quality management procedures delivered using the most rigorous working practices. It is our unique approach that makes the process both enjoyable and successful for all parties.