Masterful conversion of Grade II-listed building of archaeological importance

Redevelopment of a workshop into a day house with study and social spaces, kitchenette, shower, WC’s, lockers, and facilities for the deputy house parent and matron, including a 3-bed apartment and a separate study. Achieved BREEAM ‘Very Good’.

The project is part of the school’s £48m masterplan, which includes the Malthouse performing arts centre, Kingsdown House boarding accommodation, International College and the new Rausing Science Centre—all developed in collaboration with Skelly & Couch.

The tight site within the Conservation area of Canterbury, was chosen to provide a day house for 70 non-boarding pupils across all senior school year groups. It contains the remains of a medieval hospice, which forms one external wall and is a scheduled ancient monument, with additional ruins at the west boundary and below the footprint, also protected under the same designation. Due to its historical and archaeological context, many conventional renewable technologies were deemed unacceptable, while other planning conditions required limitations on glazing, particularly on the first floor.

The building’s form reacts to these constraints by providing an abundance of daylight and fresh air through both a glazed courtyard and a number of rooflights. A thermal energy model was developed at an early stage to inform the architectural detail, thermal performance and environmental design of operational systems. The thermal model also informed the design of a number of discreet rooflight actuators, which are controlled automatically via temperature and CO2 sensors in each study space. An overheating assessment also proved that passive night cooling could be utilised through the rooflight openings to ensure the building remains comfortable throughout the summer months.

Efficient LED lighting and daylight dimming controls significantly reduce energy consumption.

Mitchinson’s Day House prioritises sustainability through passive design to reduce energy use, while providing a highly comfortable internal environment.

Shortlisted for an AJ Retrofit Award 2019 (School category).