The conversion and refurbishment of 21 Douglas Street for Westminster School involved transforming this 5 storey masonry building from offices to accommodation for the Under School which is located across the road at Adrian House.

The building was most recently used as offices but was originally a three storey building constructed in the 1930s for the electrical coil company. It has undergone two significant transformations since then with significant changes to the elevation and the addition of an extra floor, in the form of a mansard roof, in the 1950s; then again in the 1980s when another floor was added to the mansard.

This latest transformation has created a new dining hall on the ground floor, an art department and meeting rooms on the first floor, and living accommodation for school staff on the second, third and fourth floors.

The objective was to strip the building back to a simple shell and then to refurbish it in a sustainable manner to make the building an asset to the school for the long term. The design sought to make the most of the spaces within the existing building, exploiting its large windows to make spaces that are naturally lit and ventilated.

The dining hall on the ground floor is a large volume space with high ceilings and a new roof light to the rear with high level openings, which enables this space to be naturally ventilated. Equally the art spaces are dual aspect with good levels of natural daylight that use natural cross ventilation.

The strategy from an energy point of view was to reduce consumption by improving the fabric and then to replace all the services with energy efficient systems to make the building as energy efficient as possible, within the constraints of the building fabric.