1 Bligh Street
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).

138.8 m / 455 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."

138.8 m / 455 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.

126.5 m / 415 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).

28
Below Ground

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

4
1 2 3 1 Bligh Street Outline
Height 138.8 m / 455 ft
Floors 28
Official Name

The current legal building name.

1 Bligh Street
Other Names

Other names the building has commonly been known as, including former names, common informal names, local names, etc.

Space
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, 2011
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.

Address
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
6 Star Green Star
Official Website
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
138.8 m / 455 ft
To Tip
138.8 m / 455 ft
Occupied
126.5 m / 415 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).

28
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.

96
# 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).

17
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.

45,700 m² / 491,911 ft²
Construction Schedule
2006

Proposed

2009

Construction Start

2011

Completed

Owner/Developer
Cbus Property; Dexus Property Group; Dexus Wholesale Property Fund
Architect
Structural Engineer
MEP Engineer
APP Corporation

Acoustics

G.James Glass and Aluminium Pty. Ltd

Legal

Group DLA

Paint/Coating

AkzoNobel

CTBUH Awards & Distinctions

Best Tall Building Asia & Australasia 2012 Winner

2012 CTBUH Awards

CTBUH Initiatives

Warm Weather Spaces Walking Tours 2015


17 September 2015 - Building Tour

Videos

30 October 2017 | Sydney

Tall buildings often take more than they give back, frequently exacerbating local environmental conditions, overshadowing streets and public spaces, creating wind tunnels, and impacting the...

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 1 Bligh Street

Instead of attempting to create an iconic new high-rise landmark in the heart of Sydney’s financial district, the client and design team of 1 Bligh Street desired to set new standards for site consciousness and sustainability. The new tower, located on a corner site in a densely packed district of the city, does not stand out as the tallest building in Sydney’s skyline, but instead has become well known as a welcoming and pleasant place to work that integrates well with its environment while responding directly to concerns of resource and material use.

Located at the convergence of Bligh, O’Connell, and Bent Streets, the client’s goals for the new tower were to create a flexible, efficient, and transparent design for the boxed-in site. Across Bent Street lies a public plaza, Farrer Place, to which the client hoped to preserve direct sunlight by minimizing shadows cast by the new tower. Two mid-rise, 19th-century buildings are situated adjacent to the plaza, allowing ample natural light to reach the site. However, the surrounding outdoor areas had become deactivated to public use because of the built-up and sterile nature of the business district.

In response to the site restrictions and client goals, the overall form of the building is elliptical and oriented to take advantage of the best Sydney Harbor views. The ellipse was formed in response to the Sydney grid and its termination, resolving the issue of converging street geometries. This shape also allows a dialogue with the surrounding buildings while preventing the area from feeling overly encompassed with built forms and allowing daylight to filter to ground level.

At its base, the tower is mostly open to the public, with only 40% of the overall footprint enclosed, providing an overhang for public activities. Under this canopy are a large staircase which also serves as an open public meeting spot, a children’s play area, and open-air café seating. This expansive civic space connects to the neighboring Farrer Place and has completely transformed the area, enlivening the precinct and encouraging activity.

Upon entering the ground floor of the tower, users are greeted by a soaring full-height, naturally ventilated atrium. This curvilinear space serves to bring daylight and fresh air into the core of the building, creating a unique experience for the balconies on the office floors. Eight of the tower’s fourteen lifts accessing the office floors are also placed within this atrium, each with glazed walls to provide a unique traveling experience through the light-filled space. A large winter garden with views of the harbor is located at level 15, and a large rooftop garden also provides views of the city and harbor, 28 stories above ground level.

The floor plates of the building, 1,600 square meters each, are highly efficient with a 92% net lettable to gross floor area ratio, while also providing a maximum amount of daylight to all areas. The elliptical shape minimizes distances to vertical transportation and amenities, and is 12% more efficient than rectilinear options in façade-to-floor area.

The exterior of the building is a double-skin glazed façade, which is externally ventilated to improve performance and also houses automated solar blinds to protect from direct sunlight. The façade system was designed to promote exterior views and daylighting while minimizing glare and solar heat gain. In addition, views and comfort for occupants are increased. As a significant contributor to the energy efficiency of the overall building, the façade has a shading coefficient of 0.15.

To achieve a Six Star Green Star rating, the tower also implemented several other key sustainable features. A hybrid tri-generation plant installed on the premises utilizes gas-fired power, absorption chillers, and solar-powered cooling to increase efficiency and minimize peak loads. The building is estimated to provide a 40% decrease in energy consumption over a comparable Five Star NABERS Energy Rated building.

A comprehensive blackwater treatment facility was also designed for the tower to use filtered sewer water from the municipal waste stream to flush toilets and provide makeup water for the cooling towers. This system provides 100,000 liters per day, reducing the demand on municipal potable water by 90%.

The materials used in the construction of the tower also contribute greatly to the sustainability of the building. Over 20% of the aggregate used in concrete was recycled material, and about 41% of the cement was replaced with industrial waste by-products, diverting them from traditional waste streams. Ninety percent of the structural steel has a recycled content of at least 50%. Lastly, all timber used was either recycled or from an FSC-certified source.

CTBUH Awards & Distinctions

Best Tall Building Asia & Australasia 2012 Winner

2012 CTBUH Awards

30 October 2017 | Sydney

Tall buildings often take more than they give back, frequently exacerbating local environmental conditions, overshadowing streets and public spaces, creating wind tunnels, and impacting the...

12 June 2013 | Sydney

Christoph Ingenhoven of ingenhoven architects is interviewed by Jeff Herzer during the 2013 CTBUH London Conference at The Brewery, London. Christoph talks about why he...

12 June 2013 | Sydney

Christoph Ingenhoven presents his point of view regarding the necessity of high-rises in cities. He discusses a wide range of built projects, including one of...

18 October 2012 | Sydney

Sydney’s central business district was transformed by 1 Bligh Street’s elliptical tower, which offers tenants several ground-breaking technological advances. The centerpiece is Australia’s tallest naturally...

18 October 2012 | Sydney

The 11th Annual Awards Ceremony & Dinner was held in Mies van der Rohe's iconic Crown Hall, on the Illinois Institute of Technology campus, Chicago....

18 October 2012 | Sydney

Bruce McDonald and Christoph Ingenhoven discuss the 12-year journey to make the 1 Bligh Street project a reality, as well as the details of the...

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.

12 June 2013

Christoph Ingenhoven presents his point of view regarding the necessity of high-rises in cities. He discusses a wide range of built projects, including one of the first ecological high-rises, the RWE Tower in the center of Essen as well as 1 Bligh, situated in the historical part of the financial district in Sydney, an award-winning project which set new standards regarding social, cultural, urban-planning, and sustainability. The future for most human beings will take place in cities. The reasons for this are multifaceted: geographical, ecological, and economical. The densification of cities is one of the architect’s major tasks and challenges.

1 March 2013

1 Bligh Street Chosen as Featured Building

While not the tallest building on Sydney’s skyline, 1 Bligh Street stands out for its many sustainability features, including a double-skin curtain wall.

19 October 2012

Doha Tower Named Best Tall Building Worldwide

Doha Tower was recognized as the overall "Best Tall Building Worldwide" and "Best Tall Building Middle East & Africa" in the 2012 CTBUH Awards Program.

18 October 2012

ingenhoven architects presents on 1 Bligh Street

Bruce McDonald, DEXUS Property Group, and Christoph Ingenhoven, ingenhoven architects, present on the 2012 Best Tall Building Asia & Australasia, 1 Bligh Street.

18 October 2012

Sydney’s central business district was transformed by 1 Bligh Street’s elliptical tower, which offers tenants several ground-breaking technological advances. The centerpiece is Australia’s tallest naturally ventilated skylit atrium, which soars the full height of the building. Other innovations include a double-skin, naturally-ventilated glass façade and a hybrid system using gas and solar energy to generate cooling, heating and electricity for the building.