Passivhaus

With many completed and live Passivhaus projects spanning education, leisure, healthcare, faith, residential and social housing, our portfolio runs broader and deeper than any other major UK contractor's, and includes some of the most significant Passivhaus buildings yet delivered in Britain.

Among them are the largest non-domestic Passivhaus building completed in the UK, the Centre for Medicine at the University of Leicester, the largest Passivhaus secondary school, Harris Academy Sutton, and the UK's first Passivhaus Plus primary school, Hackbridge Primary School, also in Sutton.

Recent and current projects include the Eclipse Leisure Centre in Spelthorne, the Multi-Faith Centre at the University of Exeter, student accommodation at St Peter's College, University of Oxford, and a pilot social housing scheme in Caerphilly. Now under construction in South Wales is our most ambitious scheme to date: a new primary school and community hub for Rhondda Cynon Taf County Borough Council, designed to Passivhaus, BREEAM Outstanding, WELL, Building with Nature and zero carbon in operation.

At its heart, Passivhaus is about getting the building fabric right: ultra-airtight, ultra-insulated, with mechanical ventilation and heat recovery delivering comfortable, filtered air year-round. Done well, the result is a building that uses up to 90% less energy for heating than a conventional one. With the addition of on-site renewable generation, certification at Passivhaus Plus or Premium level - as we have delivered at Hackbridge - makes it the strongest available design route to net zero carbon.

Crucially, Passivhaus buildings deliver in operation what they promise on paper. The performance gap that has dogged the construction industry, buildings using two or three times the energy designed for, is largely closed by Passivhaus's combination of fabric-first design, rigorous on-site quality control, and certification overseen by the Passivhaus Institute in Germany. We add a further layer through Energy Synergy™, our own post-occupancy monitoring service that tracks operational energy against design targets across our buildings, giving clients evidence, not assumption, that their building is performing as specified.

Passivhaus buildings are also healthier places to be. Thermal-bridge-free and draught-free construction holds surface temperatures above 17°C, eliminating cold spots and the conditions that produce mould. The ventilation system delivers filtered air as standard. For schools and healthcare environments in particular, where indoor air quality has measurable impact on concentration, absence rates and recovery, this matters as much as the energy performance.

We work alongside the most experienced Passivhaus practitioners in the country, including Architype, the UK's best-known Passivhaus architectural practice, and certifiers WARM, one of the longest-established Passivhaus consultancies and training providers in the UK.

Passivhaus Trust

Willmott Dixon is a founder member of the Passivhaus Trust, the independent body that leads adoption of the standard across the UK. We sit on technical panels, contribute to knowledge-sharing events, and have a growing cadre of Passivhaus-trained delivery staff embedded across our regional businesses, ensuring the expertise is on every project, not concentrated in one team.