Twelve years after the City of Melbourne set a high bar for sustainable buildings with Australia’s first 6 star Green Star building, Council House 2 (CH2), the council is again aiming high with a “next generation” sustainability-focused revamp of the Council House 1 site.
The $232 million redevelopment proposal for a 6 star Green Star precinct includes an underfloor carpark reserved for electric vehicles only and a geothermal heating system.
The 10-storey, 40-metre proposed development designed by Design Inc architects will result in close to a full block of new ground-floor retail space, laneway connections, commercial office space and public rooftops.
Like the CH2 before it, Deputy Lord Mayor Arron Wood said the latest redevelopment would achieve a 6 Star Green Star design and as-built rating. The plans are also shooting for Carbon Neutral Certification.
The following sustainability features are planned to be included:
- PV solar to service retail, commercial and community spaces, including panels that are integrated into the fenestration of the new building fronting Bourke Street
- end-of-trip cycling facilities
- ground-source heat exchange
- an electric vehicle-only basement
- waste management for all buildings on the site
- rainwater tanks and water sensitive urban design to capture and reuse stormwater
The revived space will also feature greenery to align with the city’s urban forest and biodiversity strategies, including green laneways, a garden atrium and green rooftops that the community can access.
The plan is to demolish the 50-plus-year-old Council House 1 building on Little Collins Street because, according to the Lord Mayor, “it’s no longer feasible to refurbish it”.
The Victorian heritage-listed former Commonwealth Bank building on Bourke Street, on the other hand, will be kept and restored.
The council wants the redevelopment to be a “new civic precinct” and include a public forum, “a large, flexible meeting space at ground level designed to encourage community engagement and participation in council activities.”
Councillors are set to vote on the plans to redevelop the site between Bourke Street and Little Collins Street next Monday.
Could more be done to become a sustainability exemplar?
Since CH2 became the first 6 star Green Star building in Australia, the rating program has been updated so that the achieving 6 star today is much harder and more comprehensive than it was 12 years ago. For example, the newest version of Green Star integrates with the International WELL Building Institute’s program to promote human health and well-being.
Dr Dominque Hes, a senior lecturer in sustainable architecture at The University of Melbourne, is still concerned that an opportunity is being missed to level up significantly on sustainability.
Although Dr Hes recognises the plans are in the very preliminary stages and only limited information is available, to be market-leading on sustainability, she suggests aiming for something like the Living Building Challenge standard – a famously tough certification where buildings must produce 105 per cent of the energy the building will need, and avoid a very long “red list” of chemicals and materials.
She said meeting Living Building standards is possible for office developments, and that the Bullitt Center in Seattle in the US is a good example.
CH2 has long been considered the City of Melbourne’s flagship building for sustainability. It features a long list of technologies designed to reduce energy use, including:
- passive chilled beam cooling
- hydronic radiant heating
- heat transfer and recovery between water loops
- phase change material tanks for thermal storage
- wind power
- solar PV and hot water
At the time it was built, the green initiatives attached to CH2 were considered particularly innovative. It was even considered a “showcase” of sustainable building features that could be used as a model for others to learn from.
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However, CH2 has also attracted critics, with some technologies, such as the wind turbines, not performing as expected.