Home to the Archbishops of Canterbury for over eight centuries, the Grade I listed Lambeth Palace is steeped in history and has marked momentous events, as well as celebrated the routines of daily life, worship, ministry and hospitality. This comprehensive reservicing programme carefully modernised critical infrastructure while respecting the fabric and character of a site that has stood since the 12th century.

The most significant refurbishment and infrastructure upgrade in over 70 years, this project has set a new benchmark in sustainable design and heritage preservation. The ambitious project enhances safety, accessibility, and environmental performance—while safeguarding the architectural legacy of one of Britain’s most treasured historic buildings.

Conservation-led, fabric-first approach and training for the future

We ensured the project embraced a conservation-led, fabric-first approach. Original building elements were retained and restored using traditional techniques and materials—preserving historical integrity while elevating performance.

Highlights include:

• Replacement of 1,450m² of floorboards
• Restoration and cleaning of 800m² of historic stonework
• Over 13,500m² of plastering and painting—an area equivalent to two football pitches

One of the most significant undertakings was the meticulous restoration of the Great Hall’s timber roof, previously damaged during the Second World War. A team of expert artisans brought it back to life, balancing historical accuracy with modern resilience.

Pioneering sustainability on a historic site

Regarded as having made industry-leading strides in its approach to sustainable design, the project embraces the General Synod’s and Church Commissioners’ commitment for the Church to become carbon net-zero by 2030. The newly installed Energy Centre marks a decisive move away from fossil fuels, paving the way for the Palace to be powered entirely by on-site renewables.

Key sustainability interventions included:

• Installation of three air source heat pumps
• Replacement of 160 windows with energy-efficient double-glazing. Typically, unachievable within a Grade I Listed building, historic drawings of the original 19th-century sash windows, which preceded the leaded casements installed after Second World War, in turn shaped the final design of the new double-glazed sash windows
• Upgrading 140 radiators, with all components salvaged and reused where possible, in line with circular economy principles

Despite the challenges posed by retrofitting a listed building, the project set the ambitious target for a BREEAM ‘Excellent’ rating. Responsible material procurement, including FSC/PEFC-certified timber, waste minimisation, and innovative construction methods contributed to strong environmental performance. A total of 39 tonnes of timber were recycled, avoiding 20 tonnes of CO₂ emissions.

Navigating complexity below and above ground

Unforeseen archaeological discoveries added layers of complexity to the programme. Excavation for the new service trench unearthed significant artefacts and remnants, including:

• 500-year-old structural walls
• Historic drainage routes and chimney bays
• Pottery fragments and clay tobacco pipes

Close collaboration with Museum of London Archaeology (MOLA) and Historic England ensured these discoveries were recorded, protected, and incorporated into revised design strategies.

Additional technical challenges included accommodating modern service requirements within the Palace’s historic fabric. Innovative rerouting of pipework and the introduction of trace heating and automatic venting systems ensured modern standards were met without compromising the integrity of original structures.

Despite the scale and complexity of the programme, Lambeth Palace remained fully operational throughout construction. The site continued to host staff, visitors, services, and international guests, including high-profile events and daily activities central to the work of the Archbishop of Canterbury.