Project description 

The history of the design decisions directly related to the construction of the Sydney Opera House remains largely anecdotal. A rich group of items recently discovered in the NSW Archive and Records may now start filling this gap. Documents brought to light include the drawings issued by the general contractor to build the concrete formwork for the shells, drawings of the temporary structures and falsework, site images, and contractor’s notes. 

While suggesting a remarkable combination of manufacturing and structural shrewdness, these archival documents call into question the canonical history of the building roof’s famous ‘sails’ and the rhetoric of the ‘spherical solution’ used to arrive at them.

‘Beyond the Spherical Solution’ is, therefore, a research project aiming to investigate the contribution of Australian contractor M. R. Hornibrook ltd in making the Sydney Opera House. The project intends to evaluate the extent of the general contractor’s design agency in the fabrication of the building through the analysis of the technical records produced throughout the building process.

The findings of this project have been presented at the 7th International Congress of Construction History in Lisbon ( and the International fib Symposium on Conceptual Design of Structures in Attisholz in 2021 (

In addition, a virtual reconstruction of Hornibrook’s design for the casting procedure of the roof segments has been completed to show the local ingenuity that empowered the fabrication of this architectural masterpiece. The video can be found here.

Project Participants

The research team comprises Dr Luciano Cardellicchio (UNSW), Dr Paolo Stracchi (University of Sydney) and Prof Paolo Tombesi (EPFL).

The casting yard of Sydney Opera House. Several moulds called ‘beds’ fabricated the 2400 roof’s pieces. Mitchell Library, State Library of New South Wales and Courtesy Max Dupain and Associates.

An image extracted by the video The Australian contribution in making the Sydney Opera House – The Casting Procedure 

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