Grimshaw designed its first commercial building in Melbourne for AGL Energy Limited (AGL). Located at 699 Bourke Street, the new AGL office is situated above the rail environment of Southern Cross Station and has been designed as an A-Grade office space making the most of the unique over-rail air-rights site.

Working closely with the developers of the building, Mirvac, and major tenants, AGL, Grimshaw has designed a workplace environment for 1500-plus employees.

Construction over rail is becoming more common in an increasingly densified Melbourne; however, these projects also present tough design and technical challenges. In a typical building construction, basements and footings allow for flexibility in the location of structure and a place to hide bulky plant equipment and services. When building in the air, a new ground plane needs to be constructed, which was done for the Bourke Street project using 2m-deep concrete-filled beams that span 20m between supports. Aligned with the western edge of the existing Southern Cross Station roof, this ground plane sits 24m above the train tracks and is the lowest occupied level of the office building accommodating the plant equipment rooms.


Grimshaw has designed the building to maximise views and daylight for the offices with 90 per cent of the space within 12m of the high-performance glazed facade, surpassing a key requirement of the 6 Star Green Star office ratings. Building occupants enjoy excellent views of the undulating Southern Cross Station roof and Melbourne’s CBD to the east as well as Mount Macedon to the north and Port Philip Bay to the south.

Conceived as part of the Southern Cross Station Master Plan designed by Grimshaw in association with Jackson Architecture, 699 Bourke Street forms a considered backdrop to the roof of the station while providing a strategic connection between Melbourne’s Central Business District (CBD) and the Docklands precinct.

According to Grimshaw Partner, Neil Stonell, the building rises 64m above the rail environment, offering an important opportunity to bring the built urban form of Docklands closer to Melbourne’s city centre. In doing so, Grimshaw’s design seeks to help unify the two precincts, delivering a building that not only responds to its urban context, but also provides premium office space in a newly created Melbourne address.

Mirvac’s Head of Cities and Urban Renewal, David Rolls describes 699 Bourke Street as an innovative and world-class building that has re-energised and redefined the workplace. Developed, constructed and owned by Mirvac in conjunction with TIAA-CREF, 699 Bourke Street’s exceptional environmental design and sustainability initiatives have been made possible as a result of the design excellence of Grimshaw Architects working in close collaboration with Mirvac, AGL and Hassell (for the tenant fit-out).

According to Rolls, the building features premium services, a 360-panel solar farm supplying 90kW of electricity (the largest solar power system on a commercial office building in Melbourne), and over 19,000sqm of net office space across nine floors. He adds that they are proud of their partnership with AGL as well as the fact that they have been able to realise another world-class workplace in the heart of Melbourne.


Design highlights of the new AGL office building at 699 Bourke Street include north facade preventing glare reflectivity onto the railyard below, using an integrated fixed-louvre screen that maintains views while preventing reflections and mitigating risk to train drivers; glazed pavilion, supported at only two points over the rail below, accommodating stairs and escalators to help identify building entrance and negotiate the 8m rise to the lowest lobby level; foyer utilising lightweight, reflective materials such as glass and stainless steel; open-air public walkway from the lobby providing a pedestrian laneway to connect Bourke Street Bridge and Collins Street; and more than 275 bike racks and 360 lockers.

699 Bourke Street was officially opened in 2015 by the Minister for Energy, Hon Lily D’Ambrosio.