The design philosophy was to use fewer, more robust components, exposed for inspection and heavily protected against corrosion. Corrosion via oxidation or electrolysis is a serious design consideration. Don't mix metal types and avoid bare metal to metal contact. All steel was galvanised then painted with two -pack. The frame is totally exposed internally and externally so any potential corrosion issues can be identified and remedied instantly. While necessary in our humid environment these features are probably over designed for most of Australia. The higher cost of materials is offset by lower labour costs and a simpler / faster build.

The computer designed bolt together frame consists of four rectangles made using 250UB31 beams. RHS cross members (125mm X 75mm X 5mm) transform the frame into a bolt-together series strong of three dimensional cubes and rectangles. The frame is surmounted by a welded steel bond beam. Panels are screwed directly onto the frame. The frame is exposed in the interior so it can be monitored and so it is isolated from the elements.Our steel beams are coloured light blue, in stark contrast with the surrounding jungle. You really have only two choices with colours; blend in or stand out. Studio Nimbus; stark white, blue and trapezoidal chooses to stand out in juxtaposition to the curves, indistinct boundaries and soft green multi-hues of the jungle.

Our frame is likely over-designed but the best we could do with engineers unfamiliar with the strength of the SIPs , but over-designed is better than under-designed. In most locations in Australia the steel specifications in the frame could be considerably pared down.

Steel uprights come in pairs of different lengths, some into deep footings and some into poured concrete slabbed roofs. This is a strategy to limit harmonic vibration of the frame in extreme weather events. All steel structures will have their own vibration frequency. In structures with repetitive steel framing vibrations could add constructively over a period of intense wind getting bigger and bigger. This can be countered by varying the lengths of the steel uprights and dampened by cross bracing. The Cyclone Shield on the balconies provides additional cross bracing and damping of vibration. (see Cyclone Design). No vibration has ever been detected so either the design is working or the design is redundant. Steel frames can conduct both heat and cold if exposed to the exterior. I avoided this heatflow by putting the majority frame inside the structure where you control the ambient temperature.