The refurbishment and extension of the Which? headquarters at 2 Marylebone Road, designed by KPF, involved substantial architectural interventions to modernise and enhance the historic building. A key element of the redevelopment was the replacement of the rear elevation with a new facade of transparent and translucent glazing panels. This contemporary treatment created a bold contrast while maintaining respect for the building’s Grade II listed 'Nash' Georgian front facade. Ergotechnics acted as executive architects in collaboration with the contractor, leading the detailed design development for the complex glazed facade. Their technical expertise ensured the successful realisation of the architectural vision, integrating performance, aesthetics, and heritage considerations.