Australia Square Tower
Sydney Australia
Height

Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the architectural top of the building, including spires, but not including antennae, signage, flag poles or other functional-technical equipment. This measurement is the most widely utilized and is employed to define the Council on Tall Buildings and Urban Habitat (CTBUH) rankings of the "World's Tallest Buildings."

1
To Tip:

Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the highest point of the building, irrespective of material or function of the highest element (i.e., including antennae, flagpoles, signage and other functional-technical equipment).

170 m / 558 ft
2
Architectural:

Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the architectural top of the building, including spires, but not including antennae, signage, flag poles or other functional-technical equipment. This measurement is the most widely utilized and is employed to define the Council on Tall Buildings and Urban Habitat (CTBUH) rankings of the "World's Tallest Buildings."

170 m / 558 ft
3
Occupied:

Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the highest occupied floor within the building.

153 m / 502 ft
Floors

The number of floors above ground should include the ground floor level and be the number of main floors above ground, including any significant mezzanine floors and major mechanical plant floors. Mechanical mezzanines should not be included if they have a significantly smaller floor area than the major floors below. Similarly, mechanical penthouses or plant rooms protruding above the general roof area should not be counted. Note: CTBUH floor counts may differ from published accounts, as it is common in some regions of the world for certain floor levels not to be included (e.g., the level 4, 14, 24, etc. in Hong Kong).

Above Ground

The number of floors above ground should include the ground floor level and be the number of main floors above ground, including any significant mezzanine floors and major mechanical plant floors. Mechanical mezzanines should not be included if they have a significantly smaller floor area than the major floors below. Similarly, mechanical penthouses or plant rooms protruding above the general roof area should not be counted. Note: CTBUH floor counts may differ from published accounts, as it is common in some regions of the world for certain floor levels not to be included (e.g., the level 4, 14, 24, etc. in Hong Kong).

46
Below Ground

The number of floors below ground should include all major floors located below the ground floor level.

4
1 2 3 Australia Square Tower Outline
Height 170 m / 558 ft
Floors 46
Official Name

The current legal building name.

Australia Square Tower
Type

CTBUH collects data on two major types of tall structures: 'Buildings' and 'Telecommunications / Observation Towers.' A 'Building' is a structure where at least 50% of the height is occupied by usable floor area. A 'Telecommunications / Observation Tower' is a structure where less than 50% of the structure's height is occupied by usable floor area. Only 'Buildings' are eligible for the CTBUH 'Tallest Buildings' lists.

Building
Status
Completed
Architecturally Topped Out
Structurally Topped Out
Under Construction
Proposed
On Hold
Never Completed
Vision
Competition Entry
Canceled
Proposed Renovation
Under Renovation
Renovated
Under Demolition
Demolished
Completed, 1967
Country

The CTBUH follows the United Nations's definition of Country, and thus uses the lists and codes established by that organization.

City

The CTBUH follows the United Nations's definition of City, and thus uses the lists and codes established by that organization.

Postal Code
2000
Function

A single-function tall building is defined as one where 85% or more of its usable floor area is dedicated to a single usage. Thus a building with 90% office floor area would be said to be an "office" building, irrespective of other minor functions it may also contain.

A mixed-use tall building contains two or more functions (or uses), where each of the functions occupy a significant proportion of the tower's total space. Support areas such as car parks and mechanical plant space do not constitute mixed-use functions. Functions are denoted on CTBUH "Tallest Building" lists in descending order, e.g., "hotel/office" indicates hotel function above office function.

office
Structural Material

Steel
Both the main vertical/lateral structural elements and the floor spanning systems are constructed from steel. Note that a building of steel construction with a floor system of concrete planks or concrete slab on top of steel beams is still considered a “steel” structure as the concrete elements are not acting as the primary structure.

Reinforced Concrete
Both the main vertical/lateral structural elements and the floor spanning systems are constructed from concrete which has been cast in place and utilizes steel reinforcement bars.

Precast Concrete
Both the main vertical/lateral structural elements and the floor spanning system are constructed from steel reinforced concrete which has been precast as individual components and assembled together on-site.

Mixed-Structure
Utilizes distinct systems (e.g. steel, concrete, timber), one on top of the other. For example, a steel/concrete indicates a steel structural system located on top of a concrete structural system, with the opposite true of concrete/steel.

Composite
A combination of materials (e.g. steel, concrete, timber) are used together in the main structural elements. Examples include buildings which utilize: steel columns with a floor system of reinforced concrete beams; a steel frame system with a concrete core; concrete-encased steel columns; concrete-filled steel tubes; etc. Where known, the CTBUH database breaks out the materials used in a composite building’s core, columns, and floor spanning separately.

concrete
4.5-STAR NABERS
Height

Height is measured from the level of the lowest, significant, open-air, pedestrian entrance to the architectural top of the building, including spires, but not including antennae, signage, flag poles or other functional-technical equipment. This measurement is the most widely utilized and is employed to define the Council on Tall Buildings and Urban Habitat (CTBUH) rankings of the "World's Tallest Buildings."

Architectural
170 m / 558 ft
To Tip
170 m / 558 ft
Occupied
153 m / 502 ft
Floors Above Ground

The number of floors above ground should include the ground floor level and be the number of main floors above ground, including any significant mezzanine floors and major mechanical plant floors. Mechanical mezzanines should not be included if they have a significantly smaller floor area than the major floors below. Similarly, mechanical penthouses or plant rooms protruding above the general roof area should not be counted. Note: CTBUH floor counts may differ from published accounts, as it is common in some regions of the world for certain floor levels not to be included (e.g., the level 4, 14, 24, etc. in Hong Kong).

46
Floors Below Ground

The number of floors below ground should include all major floors located below the ground floor level.

4
# of Parking Spaces

Number of Parking Spaces refers to the total number of car parking spaces contained within a particular building.

385
# of Elevators

Number of Elevators refers to the total number of elevator cars (not shafts) contained within a particular building (including public, private and freight elevators).

24
Tower GFA

Tower GFA refers to the total gross floor area within the tower footprint, not including adjoining podiums, connected buildings or other towers within the development.

53,000 m² / 570,487 ft²
Rankings
#
68
Tallest in Oceania
#
66
Tallest in Australia
#
18
Tallest in Sydney
#
32
Tallest Office Building in Oceania
#
32
Tallest Office Building in Australia
#
15
Tallest Office Building in Sydney
#
49
Tallest Concrete Building in Oceania
#
48
Tallest Concrete Building in Australia
#
11
Tallest Concrete Building in Sydney
Construction Schedule
1965

Construction Start

1967

Completed

Owner
Dexus Property Group; General Property Trust
Architect
Harry Seidler and Associates
Structural Engineer
Pier Luigi Nervi
Civil and Civic

Elevator

CTBUH Initiatives

Warm Weather Spaces Walking Tours 2015


17 September 2015 - Building Tour

Research

30 October 2017

Helen Lochhead & Philip Oldfield, University of New South Wales

Since 2000, through the City of Sydney’s Competitive Design Policy (CDP), the quality of major projects in the city has been improved significantly, mediating the...

About Australia Square Tower

Australia’s tallest building upon completion, Australia Square Tower was an innovative structure for its time and was among the tallest all concrete buildings in the world. The building was conceived as a two-building complex occupying an entire city block which required the demolition of nearly 30 previous structures. The taller circular building is positioned at the western end of the block, while a publicly accessible plaza and the companion Plaza Building are positioned to the east. Both structures celebrate concrete as a sculptural material with structural expressionism, the Plaza Building’s floorplates are elevated above the ground level, set upon clusters of angled pilotis exhibiting structural load transfers between the building’s rectilinear frame and the ground, meanwhile the circular, taller tower has a perimeter of exterior concrete columns, tapering as they rise with curved concrete spandrels between them and a coffered ceiling in the lobby created from a radial ribbed floor system within the concrete floor slab.

During construction, quartz concrete was pre-cast into units of standardized sizes and used not only as a finish of the exterior façade, but also as formwork for the pouring of the reinforced concrete structure, assisting in shorting the construction schedule as the building rose at an average rate of one floor every five days. The circular form of the taller tower with the externalized skeletal structure provided for a highly efficient design achieving a total floor area of 12 times the entire site area, despite a small building footprint occupying only 25 percent of the block, while also providing for a robust resistance to windloads and a high degree of solar shading. Australia Square Tower is one of Sydney’s most famous buildings and is integral part of the city’s rich architectural heritage.

30 October 2017

Helen Lochhead & Philip Oldfield, University of New South Wales

Since 2000, through the City of Sydney’s Competitive Design Policy (CDP), the quality of major projects in the city has been improved significantly, mediating the...

17 September 2015

Warm Weather Spaces Walking Tours 2015

The CTBUH Urban Habitat / Urban Design Committee organized guided walking tours of 16 cities around the globe, focusing on urban habitats around tall buildings.