Benefits of Urban Greening
Harnessing the Power of Plants
To advance its strategic goals, the City of Melbourne developed the Green Factor Tool to support designers and developers to achieve more meaningful greenery and sustainability in buildings and development.
In developing the tool, we commissioned the University of Melbourne to prepare peer-reviewed research ‘Integrating Green Infrastructure into Urban Planning: Developing Melbourne’s Green Factor Tool’. The research incorporates contextually-relevant weightings, which underpins how the Green Factor score is calculated for each development. The weightings prioritise nature-based ecosystem services which align with the City of Melbourne’s environmental strategies including the Green our City Strategy, Nature in the City, Urban Forest Strategy, Climate Mitigation, Adaptation and Water. The tool calculates a development’s greening proposal based on the ecosystem services it will provide, in alignment with our strategic priorities. This innovative approach connects the City’s values to an evidence-based methodology for assessing green infrastructure in the development sector.
The research identified green infrastructure forms and functions and prioritised functions that were locally relevant to Melbourne. It reviewed the existing evidence-base, rated the vegetation forms for relative delivery of ecosystem functions and peer reviewed the Green Factor methodology and evidence matrix.
Delivering Multiple Benefits
The identified ecosystem services which underpin the Green Factor Tool’s rigour and credibility in delivering multiple benefits are as follows:
Function Priority (highest first): Ecosystem service:
1. Urban temperature regulation (cooling) Regulating
2. Habitat for biodiversity Supporting
3. Runoff mitigation Regulating
4. Recreation Cultural
5. Place values and social cohesion Cultural
6. Aesthetic benefits Cultural
7. Food supply Provisioning
Our initiative has been implemented into our proposed Planning Scheme Amendment C376: Sustainable Building Design under the Urban Ecology category and sits alongside other important sustainable design requirements. We are currently reviewing applications that provide responses to our local planning policies and engage applicants to submit Green Factor scorecards with their responses whilst the tool is in its voluntary phase.
The City’s Bold and Innovative Vision
The aspect which sets the Green Factor Tool apart from other international examples is that it is aligned with the City of Melbourne’s strategies, and we have established the priority functions and weighted them against the different greening typologies that applicants are providing.
In addition to this, our current environmentally sustainable design local planning policies have not introduced specific requirements for green infrastructure, it has often been a component that is a ‘nice to have’. The development of the Green Factor Tool to support the proposed Planning Scheme Amendment is a step change and a broadening of sustainable design to incorporate and mandate climate adaptation components into mainstream planning processes.
Partnerships and Collaboration
The Green Factor Tool is supported by experts including landscape designers, horticulturalists, landscape architects and other experts within the greening industry. However, the critical junction is how these experts will collaborate with architects, town planners, engineers and other building experts across the development industry to support the City of Melbourne’s greening initiatives. The tool takes a holistic approach to collaboration with an interdisciplinary team of subject matter experts required to ensure the best greening and built form outcomes.
Addressing Urban Challenges
The Issue
As cities increase in size and density, the ecosystem services supplied by urban greenery and green infrastructure are increasingly vital for sustainable, liveable urban communities. However, retaining and maximising urban greenery in densifying cities is challenging. Governments have critical roles in addressing these challenges through policy development and implementation. While there’s significant attention on the quality and quantity of green space on public land, there’s an increasing focus on policy mechanisms for integrating green infrastructure in the private realm, including green roofs, walls, facades, balconies and gardens. Buildings are the biggest contributor to emissions in our municipality, accounting for 66 per cent of all our emissions. This means we must change the way we build our homes and offices to respond to the climate and biodiversity emergency.
The Impact of the Issue
The City of Melbourne declared a climate and biodiversity emergency in 2019. In doing so, we joined around 1,400 jurisdictions across 27 countries – a local and international movement recognising that climate change poses serious risks to the people of Melbourne and Australia.
The emergency acknowledges that temperature rise above 1.5°C will lead to major and irreversible damage to ecosystems. Up to one million species face extinction.
From the banks of our Yarra River / Birrarung to the trees that line our streets and world-famous parks, Melbourne’s unique environment and coveted liveability are at risk from the effects of climate change. In fact, we know climate change is already impacting Melbourne in many ways.
A Nature-Orientated Future
We know that immediate action to reduce emissions and adapt to the impacts is needed now if Melbourne is to remain a liveable city for future generations to visit, work and live in. In February 2020, the City of Melbourne’s Future Melbourne Committee endorsed 10 priority actions in response to the climate and biodiversity emergency including supporting an accelerated pathway to zero emissions by 2040. One of these actions was to mandate greening and zero emissions buildings through Melbourne’s Planning Scheme. In September 2020, the Future Melbourne Committee unanimously endorsed the Planning Scheme Amendment C376 and the Green Factor Tool.
We developed the Green Factor Tool to help developers benchmark and optimise their green infrastructure credentials for their buildings. Melbourne’s Green Factor and our proposed green infrastructure standards will improve the liveability of the city as the climate gets hotter and more extreme. The tool will increase the use of plants and nature in private developments across the city which will complement the quality and quantity of greening that we support in the public domain.
Nature Positive Solutions
Implementation
The City of Melbourne’s Planning Scheme Amendment C376 proposes to implement the Green Factor Tool as a sustainability tool into the Melbourne Planning Scheme. The proposed standards will apply to new buildings, alterations and additions that meet a certain size threshold. The standards will mean new developments in the city will need to achieve environmental targets.
The Green Factor tool was launched in May 2020 as part of the City of Melbourne’s Canopy Green Roof forum. Providing the tool as a free to use service for developers, academics, property owners and consultants to analyse their proposed landscape designs for their private sites has allowed Green Factor to be used and tested in a voluntary capacity which has demonstrated increased greening outcomes.
The first built Green Factor project was opened in 2023 and is a commercial office development in Kensington. The project has obtained a Green Factor score of 0.66 and includes a bio-diverse green roof, a feature in ground canopy tree at the street entrance, canopy trees in planters at different levels on the façade and integrated perimeter planters with balconies that provide city skyline views.
Since the Green Factor Tool was launched there have been over 200 assessments completed on a range of development types. Green Factor assessment can assign their location to be within the City of Melbourne, within partner municipalities of Merri-bek, Port Phillip and Yarra or ‘Other’ which has allowed the tool to be tested both nationally and internationally.
Feasibility
The feasibility of the Green Factor Tool has been tested via nominated planning applications where investigations into the cost and benefits of greening in the private realm were done in conjunction with other sustainable design components for our proposed Planning Scheme Amendment C376 Sustainable Building Design. Findings of this research indicated that greenery and sustainability both contribute to increased property values and reduced property spend. Proximity to green spaces was found to generally uplift property prices with the addition of tree canopy accounting for a 10% to 15% uplift in property values.
Multi-Stakeholder Support
Stakeholder support is broad and whilst the Green Factor Tool is in its current voluntary phase it is mainly supported by those involved in the design and procurement phases of development. As the proposed standards will apply across the whole municipality it will impact various typologies and interact with our diverse communities in different ways. It may be from a residential property owner who wishes to develop a single dwelling on their property, to a smaller multi-residential development where benefits may be shared amongst a smaller community, and onto large commercial or mixed use developments where office workers may enjoy increased greening as they go about their day to day business.
Management and Maintenance
The Green Factor Tool assessment asks consultants and tool users if there is a firm commitment to the development of a maintenance plan, with clear roles and responsibilities, that has been signed off by a landscape architect or similarly qualified professional. Whilst this requirement does not impact the scoring of the project it provides City officials with a clear indication of how the development should be assessed. Permit conditions are typically listed on planning applications that will require the implementation of a landscape maintenance plan which will support Green Factor assessed applications.
Measuring and Reporting Impact
Monitoring Results
Each development is tracked through the back end of the Green Factor Tool via a Green Infrastructure Database which captures an array of detail from each assessment including site information, overall Green Factor scores and green infrastructure (ecosystem services) weightings. The detail on the type of greening provided allows the tracking and identifying of trends of specific greening elements which we can tailor towards support services.
Testing the Green Factor Tool against various development types including single dwellings, townhouse developments, medium scale and large scale residential, and mixed use developments, commercial and industrial developments at varying scales was critical to ensuring the tool fits a diverse range of typologies.
Since the Green Factor Tool was launched there have been over 200 assessments completed on a range of development types. Green Factor assessments can assign their location to be within the City of Melbourne, within partner municipalities of Merri-bek, the City of Port Phillip and the City of Yarra or ‘Other’ which has allowed the tool to be tested both nationally and internationally with some assessments being conducted in Europe.
We are working with our Technology and Digital Information team to update our municipality’s Development Activity Model which provides key features and details of each development to the public. We believe that by providing the development’s Green Factor score, we can improve transparency and visibility to the broader public, which will raise awareness and build the profile of urban greening by city developments for the municipality.
www.developmentactivity.melbourne.vic.gov.au/
Demonstrating Progress
Monitoring assists in many ways. The observation of trends in green infrastructure provides appropriate levels of support to applicants. Evaluation of project locations throughout the municipality informs future precinct planning policy., And, the ability of projects to showcase their greening credentials lifts the quality of developments across the municipality.
Measuring Impact
The initiative has introduced a new way of assessing greening for private developments. We are tracking the total number of applications that are engaging with the Green Factor Tool and are also looking at the types of greening that are typical for various development typologies. We are on a journey with the Green Factor Tool as it progresses through its voluntary phase and into a regulatory status when our proposed Planning Scheme Amendment C376 will hopefully become gazetted.
Learning and Transferability
Adaption and Enhancement
In developing the Green Factor Tool, the City of Melbourne has laid the foundations to transform how developments engage with sustainability and green infrastructure to deliver greater ecosystem services and more sustainable cities and built environments.
The Green Factor Tool is an example of originality and innovation in how transdisciplinary approaches to planning can inform and support policy development for urban greening and sustainability outcomes, and lead to more rigorous, evidence-based and locally relevant outcomes.
Project governance was established by a steering group and external advisory committee. This transdisciplinary approach with policymakers, sustainability and landscape practitioners, software designers and researchers brought together unique ways of thinking, enriching Amendment C376 and the Green Factor Tool’s development journey.
The development of Amendment C376 along with the Green Factor Tool demonstrates local government leadership by providing a transformative change in how sustainability and green infrastructure are applied to the built environment. The Green Factor Tool is original and an innovative approach to building capacity, strengthening the knowledge foundations, supporting the implementation of evidence-based policy and communicating through effective engagement.
Currently, voluntary trials of the Green Factor Tool for developers in the City of Yarra, City of Port Phillip and Merri-bek City Council are being conducted to review how the tool can be applied and customised to suit other local government areas. In 2023, the City of Brisbane released its own Green Factor Tool modelled from the City of Melbourne’s.
Potential for Replication
The Green Factor Tool is part of a larger planning scheme amendment however it was identified in the Greening Our City Strategic Action Plan (GOCAP) as an integral component of this process and the level of engagement through existing planning applications has seen some unique approaches to greening in private realm. Case study examples show the tool’s applicability at various scales including the commercial office development in Kensington which is the first built project where innovative greening is demonstrated through forms including a biodiverse green roof, canopy trees both in ground and in elevated planters and balcony greening that produce a Green Factor score of 0.66. At the other end of the scale is the STHBNK development in Southbank which has only just gained planning approval but has been assessed at a Green Factor score of 1.27. This is well above the proposed minimum mandatory score of 0.55 however it shows the appetite of the development industry to push the envelope.
Inspiring Other Cities
The initiative has gone above and beyond the original scope which has reinforced the need for a Green Factor Tool for many cities to address climate change. We have engaged in trials with three other local governments in Victoria and the City of Brisbane has released a Green Factor Tool for their municipality based on the City of Melbourne’s Green Factor Tool. We are also working closely with the Council Alliance for a Sustainable Built Environment (CASBE) and they are proposing a planning scheme amendment for sustainable building design which incorporates the use of the Green Factor Tool. Their planning scheme amendment is a joint amendment with 24 local government councils across Victoria. The transfer of knowledge has been evident in most of these cases where we have had collaborative discussions on how to approach this issue on a consistent basis.
Resilience
Reducing Negative Impacts and Ensuring Sustainability
The Green Factor Tool delivers on the City of Melbourne’s ambition to increase the quality and quantity of greening in the private realm and ensure that development responds to the climate and biodiversity emergency.
It promotes resilience in the built environment by promoting the use of urban ecology and green infrastructure to reverse biodiversity loss, increase cooling and greening, reduce and improve stormwater runoff, and provide more aesthetically pleasing environments. The Green Factor Tool project has assisted the built environment profession by contributing to climate-positive design outcomes as an intrinsic part of the design and planning process for buildings and developments.
The tool promotes climate-positive design through provision of biophilic buildings and integration of greenery as a sustainability response. These contributions to the built environment are advancing the evolution of sustainability practices in a significant way by incorporating a greater focus on urban ecology for building facades and enhanced greenery on buildings that offer environmental functions in addition to greening for recreational purposes.
In 2022, the Green Factor tool won the Australian Institute of Landscape Architects inaugural national Climate Positive Design Award.
Environmental Considerations
Species diversity is considered in the tool through the weightings of functions, biodiversity is highly rated with species indigenous to the local Melbourne area generating a higher score than exotic species. This encourages developers to incorporate a diverse planting pallet into their projects that are more suited to their local climates. The tool also incorporates resources such as The Flora of Melbourne to provide guidance to applicants on what species will be more successful in their project’s region.
As the initiative is part of a larger sustainable design planning scheme amendment, its impact and interplay with other sustainable design components including energy, urban heat island, integrated water management and waste and resource recovery has been carefully considered. For instance, we have requirements for rainwater tanks to be provided in developments to ensure irrigation is provided to the proposed greening. Additionally, the Urban Heat Island requirements rely on a combination of greening and light coloured building materials, when conducted in conjunction with the Green Factor tool requirements we will see a higher amount of greening satisfying the Urban Heat Island requirement.
Use of Natural Resources
The support services that can bring a Green Factor project to life include landscape, irrigation and maintenance experts who can ensure that appropriate standards and measures are being introduced into projects from design through to implementation and operational phases. We are continually evolving processes in regard to implementation and compliance to ensure what has been committed to at the planning stage is delivered and maintained on-site. The tool rewards applicants who maintain existing greening on their sites and is considerate of soil depths to support various greening outcomes. Nature based solutions such as raingardens are also considered within the tool and provide a benefit for runoff mitigation in addition to the water quality benefits that they already provide.
