In a bid to increase the city’s urban forest, the City of Sydney has unveiled Australia’s first green roof and walls policy.
The policy is part of the city's larger Sustainable Sydney 2030 program, a series of climate change initiatives which aim to reduce Sydney's carbon emissions by 70 per cent by 2030.
Green roofs and walls improve air quality, offer biodiversity and reduce the urban heat island effect. When applied directly to a building envelope, they also work as insulation, helping to cool and heat the building, in turn reducing energy consumption. They also bring aesthetic benefits to a structure and its surroundings.
According to Sydney's new green roof policy, vegetation must cover at least 30 per cent of available rooftop space to qualify. Green walls are either free-standing or part of a building that is partially or completely covered with vegetation. The policy has a three-year implementation plan to ensure it is understood, adopted and integrated correctly.
"Green roofs and walls provide many environmental and community benefits," the City of Sydney said. "They are vital parts of a sustainable city helping plants grow and thrive on the top of buildings and vertical walls, differing from traditional gardens."
Green Roofs Australasia reports that 85 per cent of Australia's population is currently living in coastal urban areas, increasing the need for liveable and sustainable initiatives.
"As the Australian population rapidly expands towards 2020 there needs to be a vision for cities with urban greenery on buildings, canopy trees and parks which connect city living with nature," the organisation said.
In terms of Greening Sydney, the policy will support the The City of Sydney's six key objectives:
- Expanding the Urban Forest
- Greener Streets
- More Parks and Open Space
- Greening New Development and Private Land
- Green Links and Urban Wildlife Corridors
- Empowering the Community to Green the City
The city currently has 58 green roofs, five of which include a green wall, and 28 green walls, most of which are publicly accessible. There is a further 50 green roofs approved in the pipeline.
M Central at Ultimo is but one example of a successful green wall. According to the council, the wall features "deep and shallow landscapes (that) are combined with water features, barbecues and pathways to create a beautiful open parkland area for residents and visitors."
Central Park's award-winning "world's tallest" vertical garden remains the city's most prominent. The residential building features 23 green walls spanning 1,200 square metres. The greenery is made up of 35,200 plants from 383 native and exotic species and demonstrates how nature can live at any height while helping mitigate the environmental impacts of urban sprawl.
Earlier in the year, Sydney Lord Mayor Clover Moore threw her support behind greening the built environment.
“Green roofs and walls are not only beautiful additions to buildings, they also improve air quality, clean stormwater, provide a natural habitat for biodiversity and reduce power bills and greenhouse gas emissions – and the City is doing everything we can to introduce more of these features into our urban landscape,” the Moore said. “We’re seeing many more building owners and residents embracing green roofs and walls with some fantastic examples of these living systems integrated in buildings in the city.”
The 2030 plan will also extend to bringing nature into the urban public realm in the streets and squares with Sydney already committing more than $75 million to the Footway Renewal and Public Domain Landscaping programs over the next 10 years.
Beauchamp Hotel publican Sue Ritchie said the introduction of planter boxes and a new garden near her hotel at the corner of Oxford and South Dowling streets had made a huge impact on the area, known as Three Saints Square.
“The little garden and the planter boxes on all five corners of the intersection help bring the community together – it’s a simple, simple thing, but really important because it has brought happiness to the area,” she said. “Every day, instead of it being grey, urban, hard and austere, it’s just mood lifting."
Moore agreed with her assessment.
“Greener streets help improve people’s wellbeing, cool neighbourhoods and support the wildlife that calls Sydney home, such as birds, small mammals and butterflies," she said. “Streets and public spaces make up almost a third of our city area. By using these available spaces as garden beds, we can contribute greatly to increasing urban canopy, reducing the impact of the urban heat-island effect, as well as filtering stormwater before it reaches our harbour and waterways."
The City’s 10-year corporate plan, with a record $1.94 billion infrastructure program, includes major financial commitments for projects at Green Square, George Street, Barangaroo and Harold Park, providing a boost to the city’s economy, businesses and employment.
The policy will help guide developers on their greening applications in the built environment and perhaps inspire other cities around Australia to follow suit.