Seidler Offices and Penthouses (including moveable heritage)

Item details


Name of item:	Seidler Offices and Penthouses (including moveable heritage)
Other name/s:	Glen Street Offices & Apartments, Seidler Penthouse, Seidler & Associates
Primary address:	2, 2A and 4 Glen, Milsons Point, NSW 2061
Local govt. area:	North Sydney

Property description

Lot/Volume Code	Lot/Volume Number	Plan/Folio Code	Plan/Folio Number
LOT	10	DP	113743
LOT	3	DP	172924
LOT	1	DP	437535
LOT	101	DP	82409

All addresses

Street Address	Suburb/town	LGA	Parish	County	Type
2, 2A and 4 Glen	Milsons Point	North Sydney			Primary Address

Owner/s

Organisation Name	Owner Category	Date Ownership Updated
Contec Properties	General	29 Jun 04
Placemaking NSW	State Government

Statement of significance:


	The Seidler Offices and Penthouses (including moveable heritage) is of State significance as an excellent example of the work of eminent Australian architect, Harry Seidler, which demonstrates the principles of the Modern Movement. It is also a notable example of the collaboration between Seidler and renowned structural engineer, Pier Luigi Nervi, in the commercial sector. The buildings, designed in three stages between 1971 and 1994, demonstrate the evolution of Seidler's architecture, interiors, and construction methodologies over time. The buildings are unified by Seidler's architectural language and key design principles, notably that of the 'gesamtkunstwerk', the total work of art. The exterior is distinctively modernist, characterised by strong geometric forms, concrete materiality, and external sun-louvres. The buildings feature early examples of innovative T-beam structural systems and large curved concrete balconies and glass windows that provide panoramic views across Sydney Harbour. The offices of Harry Seidler & Associates and the Seidler Penthouses feature exceptionally intact, modern interiors, notable for their layout, finishes, and collection of mid-century furnishings and art. These celebrated spaces, alongside Harry's Park, have been recognised with several prestigious honours. The precinct is not only associated with Harry Seidler as architect, but as the creative offices from which his practice has operated for several decades. Seidler's influence and legacy is represented by a collection of items associated with his life and work, alongside the commemorative Harry's Park.
	Date significance updated: 20 May 25
	Note: The State Heritage Inventory provides information about heritage items listed by local and State government agencies. The State Heritage Inventory is continually being updated by local and State agencies as new information becomes available. Read the Department of Premier and Cabinet copyright and disclaimer.

Description


Designer/Maker:	Harry Seidler & Associates
Builder/Maker:	Contec Pty. Ltd.
Construction years:	1971-1994
Physical description:	The Seidler Offices and Penthouses (including moveable heritage) is a Precinct comprising three office buildings with residential components (including moveable heritage), and Harry's Park, a landscaped forecourt with sculptural elements. 2 Glen Street is the southern building (also referred to as Stage One); 2A Glen Street in the centre (Stage Two), and 4 Glen Street (Stage Three) at the north. The Seidler Offices and Penthouses comprises a Modern mid-rise office complex with elements of the International style, constructed of pre-cast and pre-stressed concrete and with external sun louvres across the principal elevations. Constructed across three decades, there is variation across the three buildings, however they share a cohesive architectural language. 2 Glen Street is on a rectangular lot and adheres to rectangular forms, while 2A and 4 Glen Street incorporate curved concrete forms, facilitated by new construction techniques which allowed Seidler to experiment with curvature. 2 Glen Street was completed in 1973 as a collaboration between Seidler and Pier Luigi Nervi. Nervi's structural system was crucial to the realisation of the open floor plan seen across each level, achieved through the use of pre-cast, pre-stressed T-beams which facilitated wide spans of floor space, as the circulation core was situated on the northern side of the building to maximise views of the Harbour. The T-Beam structure extends beyond the slab and supports the louvres. These elements are constructed of pre-cast concrete, cast in smooth steel formwork to enable a uniquely smooth finish. This is contrasted with the remainder, formed in situ in timber and resulting in a remarkably detailed timber off-board finish. 2 Glen Street is entered through a glazed ground floor foyer tiled in exfoliated granite, featuring a tapestry (one of the few non-original artworks in the building), and Seidler's 1981 Sulman Award beside the lift, which is original to the building and situated on the north side. Each level retains original fabric and an open plan layout, with the T-beams on each level creating a unique decorative ceiling element. Of particular interest is the offices of Harry Seidler & Associates, which occupy the upper two levels of 2 Glen Street and feature a distinctive, customised double storey layout. The office space is open plan, featuring a void, large windows which maximise Sydney Harbour Bridge views, and a mezzanine of pre-cast concrete accessed via concrete stairs. Crucial to the experience of the office is that the entirety of the office is partially visible, with glimpses to other spaces available, creating a sense of curiosity and movement throughout the space (Polly Seidler, personal correspondence 2025). The T-beams are not only structural, creating a distinctive ceiling pattern but contain lighting and exposed mechanical ventilation which contribute to the character of the interiors. The Seidler Offices also feature a terrace on the east side of the building accessed via the bridge which leads from the mezzanine, with additional rooftop access. Also on the upper level are seating spaces, granite conference table, and original kitchenette. The lower level features a central workstation of desks which was customised by Seidler and remains intact. All furnishings within the offices are original and were originally selected or designed by Seidler himself. This includes marble tables and Marcel Breuer tubular steel chairs. Original artworks are also retained, including works by Josef Albers and Morris Louis. The office space features several of Seidler's models, maquettes, and numerous awards. 2A Glen Street, continues the architectural language and character of 2 Glen Street, with the addition of curved faade elements on the east and west elevations. This is most notably through a curved cantilevered awning on the east elevation, while the west features sweeping curved concrete balconies and glazed windows. The sun-louvres continue along the Glen Street frontage, creating a cohesive eastern elevation, yet the west does not feature the louvres as the curvature of the elevation minimises sun exposure. The upper two levels of 2A Glen Street are the Seidler Penthouse, a double-storey apartment with exceptional modern interiors, designed by the Seidler's and with an internal connection through to the offices. This same connection point was created in the slab at the south elevation of 2A Glen Street, enabling tenants to occupy space in both Buildings 1 and 2 and provide connection as needed. The Seidler Penthouse is an open plan space with a large central void and sweeping glazed windows which provide expansive views over Lavender Bay. Central to the space is a curved concrete staircase. The lower level includes a conference space at the south side, which is the entrance between the Seidler Offices. Throughout the lower level, flooring includes a marble which was originally intended to be used at Grosvenor Place but was repurposed to the Penthouse (Polly Seidler personal correspondence 2025). The space features several photographs taken by Seidler on his travels, including photographs of his birthplace Vienna, and of the Niteroi Contemporary Art Museum in Rio de Janeiro, designed by his mentor Oscar Niemeyer. On the opposite wall are several photographs of Seidler designed buildings, taken by long-time collaborator Max Dupain. At the northern side of the Penthouse's lower level is a dining room which features a customised marble table with original Marcel Breuer tubular steel chairs and candelabra. Original artworks in the space include large pieces by Frank Stella and Roy Lichtenstein, with later additions by Lin Utzon. Behind the dining area is a sleek galley kitchen, comprising terrazzo wall tiling and timber cabinetry with sliding glass cabinet doors. Upstairs, the Penthouse features a sitting room, bedrooms and bathrooms. The upstairs level retains original carpeting, and custom timber furnishings designed by Seidler in the sitting room and bedroom, including wall-mounted cabinetry, bookshelves, and centred shelving. In the Penthouse are several maquettes, including of the T-beam detailing and Norman Carlberg sculpture at the Riverside Centre, of which there is also a 'miniature' version within the front gardens of 4 Glen Street (Stage Three). Additional details in the bedroom include floating wall-mounted bedside tables; a large Lichtenstein mural; and Fiona Lowry's 2014 Archibald Prize winning portrait of Penelope Seidler. The upper floor also features a small balcony on the east elevation. The bathroom retains original terrazzo and marble detailing and has been unmodified. Office spaces in 2 and 4 Glen Street feature a central building core, which comprise the elevator, original kitchenettes and bathrooms, with original terrazzo tiling in the bathrooms. Due to the central building core, the T-beam structure was not used in 2A and 4 Glen Street, however the sun-louvres remain present on the eastern elevation and characterise the office spaces. On the west elevation are the curved glazed windows and balconies. 4 Glen Street includes the Second Seidler Penthouse, which features much of the same features and materiality as the Seidler Penthouse on a smaller scale. Harry's Park is situated at the southern extent of the place and functions as a forecourt to 2 Glen Street. The space was designed by Seidler & Associates and is a paved pocket park with curved concrete bench seating and a large curved concrete feature at the centre, continuing the style of Seidler's work and employing his principle of curves and counter-curves. The park features drought-tolerant natives, including Angophora trees and Lomandra grasses. At the northern end directly in front of the south elevation of 2 Glen Street is a large, bold blue sculpture by renowned artist Robert Owen, named 'Tracing Light - For Harry 3D/4D'. Moveable Heritage The moveable heritage collection comprises the Sulman Medal within the ground floor foyer of 2 Glen Street; all furnishings with the Seidler Penthouses and offices of Harry Seidler & Associates; and all artworks within the Seidler Penthouses and offices of Harry Seidler & Associates (excluding the works by Lin Utzon, Fiona Lowry, and an unknown Tiwi Islands artist).
Physical condition and/or Archaeological potential:	Highly Intact and in excellent condition both internally and externally.
	Date condition updated:12 Mar 25
Modifications and dates:	1971-3 - 2 GLEN STREET 1986-88 - 2A GLEN STREET 1991-4 - 4 GLEN STREET (RAIA 2003)
Further information:	"Seidler's office building is a beautifully crafted architectural exercise which light and view using a powerful, yet rigorous, expression of structure and sun control in concrete construction to create unqiue office space that is of a quality never found in commercial office buildings. No developer would allow typical floors like these without suspended ceilings at all and all the workings of structure and services elevated to the level of museum art. Yet Glen Street, arguably Seidler's best building, is actually designed as a speculative office building with views and glass on three sides and a functional core on the fourth. The Seidler office occupies less than half the total office space." Andrew Metcalf, Architecture in Transition: The Sulman Award 1932-1996, Historic Houses Trust of NSW, Sydney, 1997. "When this building received the merit award, the jury reported, 'The design fully exploits the position, outlook and aspect of the site and the architect's own office on the top floor and mezzanine is an outstanding exercise in spatial quality and detailed design.' 'The office building standing on a cliff is strong, aloof and exclusive,' says the Sulman jury, which found it 'turning its back on the street to exploit a magnificent outlook for the benefit of the occupants.'" Architecture Australia, December 1981, 70/6, pp.16-17. (RAIA 2003)


Current use:	Offices Building & Residential Apartment – Mixed uses

History

Historical notes:

Statement of Country

Milsons Point is part of Cammeraygal Country (North Sydney Council, AIATSIS). The north shore had geographic and cultural connections to the Harbour, which was travelled via canoes and provided marine resources.

Along the foreshores of North Sydney there is evidence of Aboriginal occupation, including remains of middens, rock shelters, rock art, grinding grooves, and engravings in the sandstone country (North Sydney Council).

Milsons Point and the site

Milson's Point was named after James Milson, who was granted 50 acres by Governor Thomas Brisbane in c.1821 (Park, M., 2008). Early land use included ballast quarrying and subdivision from the 1880s (Park, M., 2008). Railway Yards were established on the foreshore by 1900, with Glen Street established on the clifftop above and freestanding and terrace houses built by the 1920s. In 1935 Luna Park opened at the site of the decommissioned railway yards. From the 1970s, development within North Sydney increased as the area positioned itself as a second business district.

Brief Biography of Harry Seidler (1923-2006)

Harry Seidler was a leading architect of the Modern Movement. He was born to a Jewish family in Vienna in 1923. The arrival of World War II and associated anti-semitic policies in Europe had major impacts on the Seidler family, prompting parents Max and Rose to leave for Australia, while Harry and his brother Marcell departed for the UK (HeriCon, 2017). Harry studied at various locations in Europe and North America in the disciplines of building, engineering, and architecture under seminal Bauhaus architects and designers Walter Gropius, Marcel Breuer, and Josef Albers. Before migrating to Australia in 1948, Seidler worked in Breuer's New York office and with Oscar Niemeyer in Rio de Janeiro. He was influenced by his mentors' works, notably the articulation of geometry and structure, and the relationship between interiors and exteriors. Other influences included engineering, art (notably Mondrian, Albers, and Stella) (Blake, P., 1973), and the works of architectural historian Sigfried Giedion (HeriCon, 2017).

Upon his arrival in Sydney in 1948 Seidler commenced his first project, Rose Seidler House in Wahroonga, which he designed for his parents. This project earnt him his first Sulman Award and launched a long career across residential, public and commercial sectors. He founded Harry Seidler & Associates, which Penelope Seidler joined in the late 1950s after retraining as an architect. He later served on the committee of the Royal Australian Institute of Architects and received the Gold Medal in 1976.

Seidler passed away in 2006, described as "a true child of the International Style without doubt, one of the best architects of his generation, anywhere" (Blake, P., 1973, 7). Harry Seidler & Associates is today directed by Penelope Seidler.

Seidler Offices and Apartments
2 Glen Street: Stage One

In NSW, the 'modern movement' began to arrive as early as the 1930s and was strengthened by the arrival of Seidler in 1948 (TKD, 2017). Much of Seidler's commercial developments were within the Sydney CBD (HeriCon 2017), however, Milsons Point in North Sydney was chosen for Harry Seidler & Associates' own offices. The first block - 2 Glen Street - was purchased by Seidler at a deceased estate auction in the early 1970s (Penelope Seidler, personal correspondence, February 2025). While the site is often perceived as a group of three cohesive buildings, it was initially only the first building at 2 Glen Street, with 2A and 4 Glen Street only purchased in later decades as the sites became available (Polly Seidler, personal correspondence, February 2025).

2 Glen Street features many of the hallmarks of Seidler's design of this period. Rectilinear in form, the 8 storey building is constructed of prestressed and precast concrete. The building is potentially the first use of prestressed and precast concrete floor beams in Seidler's works, which would later become a common feature of Seidler's commercial spaces (HeriCon, 2017). Sun-louvres were first experimented with in Seidler's work at Horwitz House, and used again at the Howard Silvers Trading building in Ultimo (HeriCon, 2017), often "applied in accordance with the orientation of the building" (Blake, P., 1973). These early examples informed the large concrete sun-louvres which were installed on the east and west facades of 2 Glen Street.

The building was innovative in its design of a semi-open floor plan (applied across each level) with vertical circulation core to the north, with a complex T-beam structure designed by Pier Luigi Nervi. The concrete beams extended beyond the glass windows of the building, supporting the sun control blades. The original architectural plans estimate the weight of each T-beam at over 11 tonnes, and reference designs of 5 louvre types (Seidler, 1971). The building exterior also featured various applications of finishes, with external precast elements finished in white, while concrete elements formed on site retain a timber board-form finish. The use of the different finishes creates stark contrast and interplay of colours and textures.
Important to Seidler was the sense of movement through spaces, veering away from static geometries, which he learned from Josef Albers (Blake, P., 1973). While the space may be categorised as open planned, only small portions of each area are visible from elsewhere within the interiors. This was a purposeful choice of Seidler's to create a sense of curiosity and movement. Internally, the space features exposed T-beam ceiling with exposed air conditioning vents. The top two floors, occupied by Harry Seidler & Associates to this day, features a mezzanine level, bridge, void and outdoor terrace.

Customised desks were established in the central workspace. Seidler himself worked towards the gesamtkunstwerk, stating that design "aims to become 'a totally integrated work of art' where interior design, furnishings, equipment and selected artworks become a cohesive whole." This was certainly achieved through the curation of furniture, including iconic tubular steel furnishings by Marcel Breuer. The use of artwork is another key element of Seidler's works, with the office space featuring original pieces by artists such as Morris Louis and Josef Albers. An Alexander Calder tapestry was installed in the lobby, however, was later stolen and replaced (Polly Seidler, personal correspondence, 18 February 2025). The building was completed in 1973, signalling exactly 25 years of practice in Australia and marking Seidler's 50th birthday (Polly Seidler, personal correspondence 18 February 2025).

2 Glen Street received the Sulman Award in 1981, with the jury noting the success of the building in "exploiting its position, outlook and aspect" (HeriCon 2017, p. 153), stating that the Seidler office in particular "was an outstanding exercise in spatial quality and detailed design" (RAIA New South Wales Chapter Award, 1981, Architecture Australia, December 1981, p. 16).

2A Glen Street: Stage Two

In the early 1980s, the adjoining lot became available and was purchased by Seidler. It was decided to construct a second stage of the offices, although by this time several conditions had changed.

2A Glen Street, completed in 1988, largely followed the form and architectural language of Stage One. However, new concrete formation techniques allowed the use of curved forms, demonstrated across balconies, cantilevered awnings, and internal stairs, being an early use of concrete curves in both Seidler's work and in Australian modern architecture broadly, as the technology was relatively new. Stage Two featured open space offices with curved balconies that faced the harbour while also being designed to maximise sun protection.

On the top floors is the Seidler Penthouse, designed to fulfill a new requirement brought in by North Sydney Council, which required all new waterside developments to include residential spaces (HeriCon, 2017). The penthouse was a collaboration between Harry and Penelope Seidler, who at this time had come to inherently know each other's stylistic preferences (Penelope Seidler, personal correspondence, February 2025). The penthouse comprised two levels, visually connected by a large central void and impressive concrete staircase which exemplified Seidler's use of curves and counter-curves. The Penthouse was the winner of the RAIA Interiors Award in 1991 and was described as a "very fine example of the mainstream of the modern movement in design", and a serene work which demonstrated the significance of architectural continuity over the "novelty of new architecture" (RAIA, 1991). Much like the Seidler Offices, the penthouse brings together architecture, interior design and art. Walls are adorned with original artworks by Frank Stella (the artist who would go on to design the iconic works at Grosvenor Place) and Roy Lichtenstein, along with photographs taken by Max Dupain and Harry Seidler. No modifications have occurred to the penthouse.

4 Glen Street: Stage Three

Finally, in the early 1990s the land at 4 Glen Street also became available and was purchased by the Seidler's. Stage Three was designed in 1991 to a design very similar to Stage Two and completed in 1994. Stage Three featured what is referred to as the 'Second Seidler Penthouse', a smaller penthouse, yet consistent in design. This has been privately leased since its completion.

Each of the commercial tenancies across all stages have been largely unmodified, retaining original spatial configurations and fabric, particularly in the kitchens and bathrooms. Overall, the three buildings have had very little modification excluding reversible tenancy fitouts.

Harry's Park

In 2006 Harry Seidler passed away and an agreement was made with Crown Lands to commemorate his memory at the neighbouring park, establishing Harry's Park. Designed by Seidler & Associates, with landscape design by Bruce Mackenzie and a large geometric sculpture by Robert Owen, Harry's Park acts as a forecourt to 2 Glen Street. Completed in 2011, Harry's Park has been awarded several prestigious awards including the Australian Institute of Architects (NSW) Urban Design Architecture Award (2012) and a Commendation in the CCAA National Public Domain Award 2013.

Historic themes

Australian theme (abbrev)	New South Wales theme	Local theme
4. Settlement-Building settlements, towns and cities	Accommodation-Activities associated with the provision of accommodation, and particular types of accommodation – does not include architectural styles – use the theme of Creative Endeavour for such activities.	Architectural design-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Architectural styles and periods - 20th century Modern Movement-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Designing in an exemplary architectural style-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Architectural styles and periods - late 20th Century Late Modern-
8. Culture-Developing cultural institutions and ways of life	Creative endeavour-Activities associated with the production and performance of literary, artistic, architectural and other imaginative, interpretive or inventive works; and/or associated with the production and expression of cultural phenomena; and/or environments that have inspired such creative activities.	Architectural styles and periods - International Style-

Assessment of significance


SHR Criteria b) [Associative significance]	The Seidler Offices and Penthouses (including moveable heritage) is a State significant precinct for its association with seminal Australian architect, Harry Seidler, and his practice, Harry Seidler & Associates. Seidler is widely considered one of Australia’s most influential architects of the 20th century, having received several awards, including multiple Sulman and Wilkinson Awards and the RAIA Gold Medal. He is recognised as a leader of the Modern Movement, and frequently credited with bringing the Bauhaus and Internationalist styles to Australia following his emigration in 1948. The Seidler Offices and Penthouses (including moveable heritage) is of State significance as it was designed for Seidler’s own architectural practice and use, and therefore reflects Seidler’s style and broader design principles. Further, it is of significance as the place from which he operated his practice for several decades. The Harry Seidler & Associates office and the Penthouses feature a collection of moveable heritage items demonstrating Seidler’s long and exceptional career, including architectural awards, models, maquettes, artworks, and furnishings by Seidler’s collaborators and mentors Marcel Breuer, Josef Albers, Frank Stella, and Max Dupain. Additionally, the Seidler Penthouse at 2A Glen Street features personal items, including photographs taken by Seidler on his travels and Fiona Lowry’s 2014 Archibald Prize winning portrait of Penelope Seidler. Since 1973, Harry Seidler & Associates has been based at the Seidler Offices, (now operated by Seidler’s wife and collaborator, Penelope Seidler) demonstrating the continuous connection of Seidler’s practice to the place. Harry’s Park, named after Seidler to commemorate his death, epitomises his legacy as a giant of Australian architecture.
SHR Criteria c) [Aesthetic significance]	The Seidler Offices and Penthouses (including moveable heritage) is of State significance as an excellent example of a Modern Movement commercial building designed by renowned architect Harry Seidler. Designed in three stages between 1973 and 1994, it is a precinct which demonstrates the evolution of Seidler's architecture, embracing new structural advancements and construction techniques while maintaining a unified architectural language and form. The Seidler Offices and Penthouses (including moveable heritage) is considered to demonstrate the key characteristics of the Modern and Internationalist movements broadly, along with Seidler's principal design traits and philosophies. The buildings are characterised by a strong geometric form which creates visual opposition, concrete materiality, and the connection between interiors and exteriors. Sited overlooking Sydney Harbour, large windows maximise views and light, controlled by innovative sun-louvres often seen in Seidler's works. Comprising considered design across architecture, interiors, art, and landscape, it is an excellent example of the gesamtkunstwerk, or 'total work of art', which was a defining principle of Seidler's work. The Seidler Offices and Penthouses (including moveable heritage) is an early, notable collaboration between Seidler and esteemed structural engineer, Pier Luigi Nervi. Nervi's innovative T-beam structural system facilitated the open-plan interiors, supported the sun-louvres, and created a distinctive internal ceiling pattern. For its design excellence, 2 Glen Street was awarded the 1981 Sulman Medal. 2A Glen Street, completed in 1985, is an early example of Seidler's use of curved concrete across the balconies and internal staircase of the Seidler Penthouse. These features were enabled by new techniques in concrete formation and glass manufacturing which revolutionised Seidler's work and allowed him to experiment with new geometric forms. The Seidler Penthouse is an iconic residence, featuring striking modernist interiors, art collection, and custom furnishings, for which it was awarded the RAIA Interiors Award.
SHR Criteria f) [Rarity]	The Seidler Offices and Penthouses (including moveable heritage) demonstrate rarity at a State level for the precinct’s finely detailed construction, and the design interest and integrity of the interiors at both Seidler Penthouses. The Seidler Penthouse at 2a Glen Street is a rare example of intact modernist interiors. It is of exceptional design interest for its application of curved, panoramic windows, sweeping central staircase, and palette of contemporary colours, materials, and finishes. Both penthouses (at 2 and 2A Glen Street) are rare examples of intact, finely detailed, well-appointed apartments designed by Seidler. They exemplify his tastes in interior design, which could be fully explored as the building was for Seidler’s use. The interiors have been retained as they have remained in Seidler ownership. The use of a T-beam structural system in a mid-rise commercial context is rare at the State level.
SHR Criteria g) [Representativeness]	The Seidler Offices and Penthouses precinct (including moveable heritage) is representative at a State level as an excellent and relatively early example of commercial office spaces and modernist apartments designed by Harry Seidler with Pier Luigi Nervi. The precinct includes three fine Modern Movement buildings which demonstrate the principles of the style and of Seidler’s works, including geometric forms, concrete construction open layout, and strong consideration of interiors. The buildings demonstrate remarkable integrity, however the Harry Seidler & Associates Office and the Seidler Penthouses are considered exceptional for their ability to express Seidler’s design intent and principles. Original finishes and materials, custom furnishings, furniture by notable designers including Marcel Breuer, and artworks by Josef Albers, Morris Louis, Frank Stella, and Roy Lichtenstein, remain in situ, as selected and styled by the Seidler’s for their own space.
Integrity/Intactness:	The buildings have remained in the ownership of the Seidler family and as such, retain an exceptional degree of integrity both internally and externally. Very few modifications - beyond reversible tenant fitouts - have occurred. The integrity of the place is particularly remarkable within both Seidler Penthouses and the offices of Harry Seidler & Associates, which retain original finishes, furnishings, and artwork selections.
Assessment criteria:	Items are assessed against the State Heritage Register (SHR) Criteria to determine the level of significance. Refer to the Listings below for the level of statutory protection.

Procedures /Exemptions

Section of act	Description	Title	Comments	Action date
57(2)	Exemption to allow work	Standard Exemptions	HERITAGE ACT 1977 ORDER UNDER SECTION 57(2) TO GRANT STANDARD EXEMPTIONS FROM APPROVAL I, Penny Sharpe, the Minister for Heritage, on the recommendation of the Heritage Council of New South Wales and under section 57(2) of the Heritage Act 1977: revoke the order made on 2 June 2022 and published in the Government Gazette Number 262 of 17 June 2022; and grant an exemption from section 57(1) of the Act in respect of the engaging in or carrying out the class of activities described in clause 2 Schedule A in such circumstances specified by the relevant standards in clause 2 Schedule A and General Conditions in clause 3 Schedule A. This Order takes effect on the date it is published in the NSW Government Gazette. Dated this 29th day of October 2025 The Hon Penny Sharpe MLC Minister for Heritage For more information on standard exemptions click on the link below.	Nov 7 2025
57(2)	Exemption to allow work	Heritage Act - Site Specific Exemptions	Exemption order for Seidler Offices and Penthouses (including moveable heritage) listing on the State Heritage Register (SHR 02118) under the Heritage Act 1977 I, Penny Sharpe, the Minister for Heritage, on the recommendation of the Heritage Council of NSW dated 2 September 2025, make the following order under section 57(2) of the Heritage Act 1977 (the Act) granting an exemption from section 57(1) of the Act in respect of the engaging in or carrying out of any activities described in Schedule C by the owner, manager, mortgagee or lessee (or persons authorised by the owner or manager) of the item described in Schedule A on the land identified in Schedule B. This order takes effect on the date it is published in the NSW Government Gazette. Dated this 4th day of November 2025. The Hon Penny Sharpe MLC Minister for Heritage SCHEDULE A The item known as Seidler Offices and Penthouses (including moveable heritage) SHR 02118, situated on the land described in Schedule B. SCHEDULE B The item known as Seidler Offices and Penthouses (including moveable heritage) SHR 02118, located as identified on the plan catalogued Heritage Council Plan 3349 in the office of the Heritage Council of NSW. SCHEDULE C The following specified activities/ works to an item do not require approval under section 57(1) of the Act. The follow exemptions apply in addition to the ‘standard exemptions’ for items listed on the State Heritage Register made under section 57(2) of the Heritage Act 1977 and published in the NSW Government Gazette. GENERAL CONDITIONS These general conditions apply to the use of all the site specific exemptions: a) Anything done under the site specific exemptions must be carried out by people with knowledge, skills and experience appropriate to the work (some site specific exemptions require suitably qualified and experienced professional advice/ work). b) The site specific exemptions do not permit the removal of relics or Aboriginal objects. If relics are discovered, work must cease in the affected area and the Heritage Council of NSW must be notified in writing in accordance with section 146 of the Heritage Act 1977. Depending on the nature of the discovery, assessment and an excavation permit may be required prior to the recommencement of work in the affected area. If any Aboriginal objects are discovered, excavation or disturbance is to cease, and Heritage NSW must be notified in accordance with section 89A of the National Parks and Wildlife Act 1974. Aboriginal object has the same meaning as in the National Parks and Wildlife Act 1974. c) Activities/ works that do not fit within the exemptions described in this document or the ‘standard exemptions’ for items listed on the State Heritage Register made under section 57(2) of the Heritage Act 1977, and published in the NSW Government Gazette would require an approval under the Heritage Act 1977. d) The site specific exemptions are self-assessed. It is the responsibility of a proponent to ensure that the proposed activities/ works fall within the site specific exemptions. e) The proponent is responsible for ensuring that any activities/ works undertaken by them, or with their landowners consent, meet all the required conditions and have all necessary approvals. f) Proponents must keep records of any activities/ works for auditing and compliance purposes by the Heritage Council of NSW. Where advice of a suitably qualified and experienced professional has been sought, a record of that advice must be kept. Records must be kept in a current readable electronic file or hard copy for a reasonable time. g) It is an offence to do any of the things listed in section 57(1) of the Heritage Act 1977 without a valid exemption or approval. h) The site specific exemptions under the Heritage Act 1977 are not authorisations, approvals, or exemptions for the activities/ works under any other legislation, Local Government and State Government requirements (including, but not limited to, the Environmental Planning and Assessment Act 1979 and the National Parks and Wildlife Act 1974), or construction codes such as the National Construction Code. i) The site specific exemptions under the Heritage Act 1977 do not constitute satisfaction of the relevant provisions of the National Construction Code for ancillary works. Activities or work undertaken pursuant to a site specific exemption must not, if it relates to an existing building, cause the building to contravene the National Construction Code. If additional activities or work is required to comply with the NCC, an approval under the Heritage Act 1977 may be required. j) In these exemptions, words have the same meaning as in the Heritage Act 1977 or the relevant guidelines, unless otherwise indicated. Where there is an inconsistency between relevant guidelines and these exemptions, these exemptions prevail to the extent of the inconsistency. Where there is an inconsistency between either relevant guidelines or these exemptions and the Heritage Act 1977, the Act will prevail. k) Where relevant The Heritage Manual (1996, Heritage Office and Department of Urban Affairs and Planning) and The Maintenance Series (1996 republished 2004, NSW Heritage Office and Department of Urban Affairs & Planning) guidelines, or any subsequent documents prepared to replace or supplement these documents, must be complied with then undertaking any activities/ works on an item. EXEMPTION 1: APPROVED WORKS Specified activities/ works: a) All works which form part of any existing development consents active at the time of listing on the State Heritage Register. EXEMPTION 2: OPERATIONAL ASPECTS – EXTERNAL WORKS WITHIN CURTILAGE Specified activities/ works: a) All works which do not impact significant fabric of the precinct, within the curtilage of the item, relating to: i. Maintenance, upgrade, repair, or replacement of footpaths and other civil works like-for-like or with sympathetic alternatives. ii. Maintenance, upgrade, repair, or replacement of site security like-for-like or with sympathetic alternatives. iii. Removal of existing plantings and addition of new plantings in garden areas excluding Harry’s Park, and replacement of vegetation including within Harry’s Park. Within Harry’s Park, vegetation replacement should be either like-for-like or sympathetic in character, and adhere to the existing landscaping character and design. EXEMPTION 3: TENANCY FITOUT WORKS AND COMMERCIAL SPACES Specified activities/ works: a) Works which would have no adverse impact on the heritage significance of the precinct, within the curtilage of the item, relating to: i. Demolition of internal fitouts including lightweight partition, floor finishes, false ceilings (in 2A and 4 Glen Street only), and associated services to office, and retail and commercial areas. This excludes works to bathrooms and kitchenettes throughout 2, 2A and 4 Glen Street other than minor works outlined below (part iii). ii. Construction of new fitouts and alterations to existing fitouts, including lightweight partitions, new floor finishes, new ceilings (excluding within 2 Glen Street), and or associated services to office, retail and commercial areas. Significant spaces and their volumes, the entry lobby, lift lobbies, and stairs should not be decreased in size or adversely affected through the introduction of partitions. iii. Like-for-like or sympathetic replacement of non-significant kitchen and bathroom fittings and fixtures when required, such as tapware, plumbing, toilets, and sinks. iv. Creation or closure of openings to connect tenancies across buildings (with landowners consent), where indicated by cut lines in existing concrete walls, as designed by Seidler. This excludes closure of the existing opening between the offices of Harry Seidler and Associates and the Seidler Penthouses. At least one example of the cut line must remain intact and unaltered. v. Works associated with maintenance of terraces and balconies, including maintenance and new fixtures, fittings, landscaping, furniture, and finishes as required, where there would be no adverse heritage impact. vi. All lift maintenance and repair works, or sympathetic lift replacement which adheres to existing spatial volumes in 2A and 4 Glen Street. EXEMPTION 4: MOVEABLE HERITAGE Specified activities/ works: a) Maintenance and conservation of moveable heritage elements, including artworks, furnishings, and architectural collections (maquettes, models, plans).	Nov 7 2025

Standard exemptions for engaging in or carrying out activities / works otherwise prohibited by section 57(1) of the Heritage Act 1977

Listings

Heritage Listing	Listing Title	Listing Number	Gazette Date	Gazette Number	Gazette Page
Heritage Act - State Heritage Register	Seidler Offices and Penthouses (including moveable	2118	07 Nov 25	461	30
Heritage Act - State Heritage Register	SHR No. 2118 Seidler Offices and Penthouses (inclu		07 Nov 25
Local Environmental Plan	North Sydney Local Environmental Plan 2001

References, internet links & images

Type	Author	Year	Title
Written		1991	Architecture Australia, Best Interiors Award, Nov 1991
Written		1981	Architecture Australia, Dec 1981, 70/6
Written	Andrew Metcalf	1997	Architecture in Transition: The Sulman Award 1932-1996
Written	Dennis Sharp	1997	The Master Architect Series III: Harry Seidler – Selected and Current Works
Written	Graham Jahn	1997	Sydney Architecture
Written	HeriCon Consulting	2017	The Architecture of Harry Seidler: A Report for the Heritage Council of NSW
Written	Kenneth Frampton & Philip Drew	1992	Harry Seidler: Four decades of Architecture
Written	Peter Blake	1973	Architecture for the new world: the work of Harry Seidler
Written	Royal Australian Institute of Architects	2003	Harry Seidler and Peter Muller Buildings on the RAIA (NSW) 20th Century Register of Significant Buildings Nominated for the NSW Heritage Register
Written	TKD Architects	2019	Modern Movement Architecture in Central Sydney: Heritage Study Review
Written	Tony Brassil, Robert Irving, Chris Pratten, Conybear	1993	North Sydney Heritage Study Review, No 1327

Note: internet links may be to web pages, documents or images.

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Data source


The information for this entry comes from the following source:
Name:	Heritage NSW
Database number:	5055653
File number:	H04/00293 H03/00117-002

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