Patera was conceived as a mass produced system for standardised buildings. Designed with structural engineer Anthony Hunt for client Nigel Dale, the building system was delivered to sites in containers as kits of parts. Each building kit could be erected on a prepared concrete ground slab in just ten days by a team of three using a forklift truck.

The prototype design, built alongside the component factory, enclosed a floor area of 216 sq m. Its concept was a simple box rising more than 3.5 metres with a wraparound steel envelope and glazed gable ends. The tubular steel lattice structural frame was placed outside the external envelope, utilising three-pin portal frames. These support the roof trusses with the help of a special hinged rod capable of withstanding tensile stress.

The same type of steel panel was used for both the wall and roof, and could be replaced with windows. These panels consist of mineral fibre insulation between two skins of ribbed, pressed steel supported by rectangular purlins. Joints are sealed by gaskets, and wiring and water pipes run through ducts within the thickness of the wall.

Patera was used to create a number of demountable structures built during the 1980s. One was relocated to serve as part of Hopkins’ own office in Marylebone, where it sits alongside a larger structure inspired by the standard Patera design. The latter iteration accommodates the inclusion of a mezzanine floor, and introduces glazing into the roof. Instead of the portal frame structure, the frame is supported with ordinary trusses on tubular steel columns.