The final form of the roof features vaulted shells created from spherical geometry.
Late in 1961, a letter to the Dean of the Faculty of Architecture at the University of Sydney, Professor Harry Ashworth, reflects Utzon's optimism for the new design:
"We were riding two horses for a long time. The last six months the real solution for everything technically and aesthetically was developed and it was even the cheapest way of making it you could dream of ... Of course, all the work during the past three years has been the background for arriving at this magnificent solution."
In 1962 – more or less five years since the winning design was announced – the finished form of the roof scheme of Sydney Opera House was revealed to the public for the first time.
Despite minor adjustments until the start of construction, the iconic profile of the Sydney Opera House is instantly recognisable in these drawings.
The unity of architect Jørn Utzon's vision is apparent in these drawings, this cross-section articulating the relationship between the shells and the form of the Minor Hall.
Utzon had designed the form of the glass walls based upon the iterative natural form of the movement of an eagle's wing. This idea became the basis for the curtained form seen here.
Utzon's designs for the glass walls were, however, never realised. The glass work seen today is a result of interpretation and collaboration between architect Peter Hall and the engineers of Arup.
This cross section of the Major Hall again illustrates Utzon's design ideals, based on natural forms. The architect likened this cross-section to opening a walnut and being both surprised and delighted by the coherence of difference in form.
The tessellated ceiling scheme of the Major Hall was never realised. It was instead abandoned for a design based upon a motif of breaking waves that reflected Utzon’s ill-fated attempt to accommodate adjustments to seating numbers at the insistence of the Australian Broadcasting Corporation late in the project.
The stage machinery indicated here was installed but then demolished and removed from the building after Utzon was compelled to leave the project in 1966; he was replaced by a committee of architects led by Peter Hall.
The unique point of intersection of the axes of the halls is seen in this elevation and can be precisely stood upon to this day.
The point is singular in the overall geometry of the building, an intersection of the axes of both the halls and the overall grid system for the site.
From this point, one can look directly down the centre lines of both halls.
The position is marked by the Inaugural Plaque, laid in 1958 at a ceremony to commemorate the beginning of construction of the podium.
If you visit the site, be sure to seek it out, set into the first set of the Monumental Steps.
This exquisite drawing of the spherical geometry was completed at the end of 1961 in Hellebæk, Denmark, by resident architect Rafael Moneo, who later became one of Spain's most famous architects and winner of the prestigious Pritzker Prize in 1996.
Almost 1 million tiles adorn the roof of the Sydney Opera House, their uneven glazed surfaces scattering light across the patterned array and effortlessly narrating the geometry of the roof, communicating its grand complexity in a beautiful and deliberate finish.
These tiles are adhered to so-called tile lids, pre-cast chevron forms with spheroidal curvature to continue the curved surface of the roof.
Created by Sam Doust and the
Sydney Opera House GCI Team
State Records NSW