The hardest part here has to be getting a curved ceiling to read as one smooth surface when the sheet material only comes in 2.4m panels. The maker handled that with shadow joints built from 18mm ply and 9mm material, layered so the joints look deeper than they really are. A suggestion of 12mm throughout came up along the way, but the layered approach apparently gave the better result.
The whole lining took 84 sheets of Tricoya MDF. Every sheet was double primed before installation, with all cuts sanded, edged and primed, then numbered and taken back down for another coat before going up for good. Fixing was 50mm stainless screws at 300mm spacing plus Sikaflex 11-FC adhesive, and the screw holes were filled with 2-part epoxy, sanded, painted, filled again, sanded once more, then finished with two coats of marine grade paint.
What stands out to me is the joint pattern itself: radiating seams and concentric arcs that run from an exterior cantilevered overhang through the glass facade and keep flowing inside, lining up across hallways and corner glass bays. A rotary laser level on a tripod was on site to keep everything true, and the maker reckons the frame holds more steel than can be imagined.
The open question is durability. At $500 AUD per sheet this was not a cheap gamble, and the maker openly admitted not trusting MDF outdoors, so an offcut went into a bucket of water for two weeks as a test before any priming started. That kind of scepticism before committing 84 sheets seems like exactly the right instinct to me.