The Sydney Harbour Federation Trust has appointed Lahznimmo Architects for the design development phase of the former HMAS Platypus site at North Sydney, which has been closed to the public for more than 150 years.

According to Andrew Nimmo, director at Lahznimmo Architects, “The Platypus site is a unique place.  It has a fascinating history with industrial buildings that lend themselves to creative and innovative reuse. Once complete the site is sure to be a landmark destination on the harbour for the people of North Sydney.”

Specialising in public projects, Lahznimmo Architects are well versed in the adaptive reuse of heritage buildings to create appealing public spaces having delivered St James Station CafĂ© in Hyde Park, City of Sydney Council’s Easy Sydney Community Art Centre and the Armory Wharf at Blaxland Park, Sydney Olympic Park. They will be joined by landscape architectural firm Aspect Studios.

"For many people Platypus is something of a mystery. It is tucked away on the edge of North Sydney fronting Neutral Bay and has been closed to the public for most of its 150 years of developed history,” Nimmo says.

“Most recently it was Australia's only dedicated naval base for submarines, and was where they assembled torpedos - but few would know that history. I hope that the public will gain an understanding of the fascinating layered history of the site, and a broader appreciation of the history of the working harbour."

“It’s an exciting phase for the project following a significant period of planning and community consultation and the remediation works,” says Mary Darwell, Sydney Harbour Trust CEO.

“While the industrial heritage values of the buildings will be retained, the buildings and public spaces will be adapted and opened up to suit new uses with a mix of cultural, community and commercial uses expected,” she says.

HMAS Platypus was formerly a gasworks factory that was partially resumed by the Commonwealth Government as a torpedo manufacturing facility during WWII. In 1967, it became the base for the Royal Australian Navy’s Oberon Class submarines and was renamed HMAS Platypus.

The Harbour Trust wants to revitalise the site with new open space and urban parkland as well as adaptively reusing the buildings to create commercial and public spaces and includes a number of works to enable the site to be opened to the public including:

• New public open space: creating new open space on the foreshore and facing High Street.

• Access improvements: a new over-water pedestrian link to Kesterton Park, new lift and stairs between levels, limited new car parking accessed from High Street, and road safety improvements to Kiara Close,

• Building renovation: base refurbishment of selected buildings to facilitate their future re-use.

To say that the architects are excited to be given the opportunity to work on such an iconic site would be an understatement says Nimmo.

"Any architect who has the opportunity to work on a site of this scale on the harbour is going to feel pretty excited.”

“Even better, our brief is to make this site publicly accessible and give it a new and active life through adaptively reusing the industrial structures," he says.

In its current state, HMAS Platypus seems isolated and disconnected from the rest of Sydney. Currently missing are the pedestrian linkages that will weave the site into its local and regional context. Within the site, the many level changes make universal access difficult and orientation unclear.

CEO Darwell says that “Conceptually, all architectural injections into the site aim to be non-invasive and ‘touch the site lightly’, retaining both the existing industrial language and ecological ecosystems found on the site. “

“Minor interventions to assist in the accessibility and orientation around the site such as a new lift, ‘clip-on’ cliff side walkways, stairs and bridge links are all imagined as a lightweight framed and clip-on family of forms – clearly modern, but taking their cue from the structural expressive of the industrial buildings.”

“Central to the site’s renewal is the proposed removal of the RANTME Office Building, (Building 3), to create a new public plaza - ‘Arrival Square’. Arrival Square becomes the front door of the site. This is where all the arrival paths converge, providing a central place for site interpretation and exploration to commence. It provides an important breathing space between the [industrial] FIMA and RANTME buildings and opens up a significant view corridor along the road cutting from High Street,” she says.