The building is predominantly masonry construction. Floors are either reinforced concrete or timber on steel beams and cast-iron columns. Converting the basement into a carpark necessitated excavation of the courtyard and replacing perimeter brick piers with steel picture frames which redistribute loads to the existing foundations. The new courtyard floor is supported by five steel columns. Precast concrete slabs span between steel beams, overlaid with reinforcement and an in-situ slab.
The lift tower, south-facing balconies and decks are constructed with steel, chosen for structural economy and speed of assembly. The lift tower is constructed in two sections: an in-situ concrete base rises one and a half storeys, with a steel frame, bolted to the outside, rising the remaining five. To avoid bracing in the tower, the necessary bracing was provided by horizontal beams spanning the courtyard and diagonal bracing in the decks.
Superimposed onto the north wall of the courtyard a four storey frame supports south-facing balconies. This is supported at the corners and by an intermediate perpendicular frame resting on the new basement structure. Remaining decks are constructed using paired steel I sections. The desire to avoid vertical supporting structure resulted in a cantilevered solution.
The single skylights to the west are supported by a pair of portals which span the trimmed opening. These rest on the existing beams. On the south side, the pair of portals are braced by a single channel used to pick up the roof and to restrain the glazing. As the remaining three elevations are glazed, the north wall and roof are infilled with a timber frame and sheathed in ply to prevent racking. The paired east roof skylights are half skylit, and glazed to the west. A steel portal frames the west-facing elevation. Two further portals, coupled, span at the midpoint of the roof either side of the gutter. The remaining elevations are simply framed in timber, sheathed in ply and clad in zinc.