Exoskeleton
The defining visual quality of Powerhouse Parramatta is the white steel latticing that surrounds it.
Expressed in three levels of scale and complexity, with the steel members reducing in size and refining as the building rises, this lattice design forms both the building’s façade and, crucially, its supporting structure – its exoskeleton.
The geometry of the lattice structure greatly reduces the amount of material needed to support the building’s physical load.
It also lightens the visual presence of the steel.
Even at ground level, where the lattice columns are at their thickest, they serve to filter light – a filtering that continues all the way up the building and through the interplay between the different geometries.
The exoskeleton is important to the way the building communicates.
Moreau Kusunoki wanted to present a neutral exterior that is open to everyone.
Its white-painted steelwork creates an envelope that expresses the building’s structure very clearly and honestly, emphasising a feeling of accessibility.
The latticed design makes for extreme transparency, so that activity and movement within animates the building from the outside.
This is important to the Powerhouse Parramatta vision which highlights a porous relationship with the surrounding neighbourhood and a culture of welcome and inclusivity.
It also serves as a means of keeping the building’s elements at a human scale.
This is very different from a more conventional steel and concrete structure, which can make a human standing beside them feel fragile.
Here, the smaller steel members, as you rise up the building, can be grasped in the hand.
At the same time, without the need for columns, the interior leaves the spaces and circulation areas free of physical interruptions.
The lattice design emerged out of discussions between Nicolas Moreau, Hiroko Kusunoki and the distinguished Tokyo University professor of engineering, Jun Sato, whose initial sketches were key to defining its geometry. The exoskeleton is being realised with the hands-on expertise of ARUP Engineer Kengo Takamatsu.
It is possible to note a reference to Sydney Harbour Bridge in the lattice structure. The echo was not present in the initial idea, but it is undoubtedly there, with an interesting comparison implicit in the environmental story (see below). The influence of Centre Pompidou, close to Moreau Kusunoki’s Paris office and standing as a ground-breaking model for a museum building with an external structure, is also acknowledged.