As our cities continue to become bigger, are we losing the quality of our homes?
Would having access to gardens and green space at high density help make our cities more liveable?
Would living architecture help re-balance the liveability of Australian cities?
I think it could, provided apartments gardens are well-designed and a commitment is made by developers and bodies corporate to keep them alive, but the costs need to be put alongside the benefits to enable this.
Living architecture is an all-encompassing term for green roofs, walls and facades, which are used as a way of adding plants directly onto buildings.
The greening of cities is increasingly being recognised as a remedy for some of the problems that urbanisation and climate change are causing. More than ever, people are responding to the evidence that more greenery in our cities can provide tangible benefits.
We now have the technical ability to deliver living architecture successfully in Australia. This is evidenced by the number of successful green roof, wall, and facade projects that have been completed here recently.
Despite this, Australia is not seeing the kind of proliferation of green roofs, walls, and facades that is occurring in other countries.
The question is: why not?
If we can address some of the costs and benefits of living architecture, we may re-balance the liveability of our cities by encouraging more green roofs, walls, and facades.
Developers will provide the market with buildings that sell, but they need to make a profit. They tend to only build amenity that yields direct returns on their investments. Accordingly, elements such as swimming pools and elaborate decorative facades are included if it is perceived they will increase demand and therefore boost the property value.
We are seeing some greenery incorporated into buildings, but not at the scale and frequency that will make a real difference to liveability.
For example, the recently released Arden Park development in North Melbourne is being marketed with a significant rooftop park.
Presently, the returns for elements such as this need to be justifiable if not directly measurable and must accrue to the building owner so that the value of the property increases. Presumably for the developers of Arden Park, the benefits for the rooftop park have been assessed positively in terms of increasing demand for the property, such that they are seen to outweigh the costs.
This cost-benefit analysis of greening our cities emphasises private benefits while the public benefits are not factored in to the developer’s ledger.
Governments seek to ensure what is built serves the needs of the people but they cannot, nor should they, dictate on all matters. They can encourage more green roofs with overarching statements such as those within Plan Melbourne. However, they have not yet reached the point where green roofs are mandatory as is the case in Germany, Toronto, and Chicago.
Governments are motivated by perceived public benefits, but the cost needs to be justifiable, otherwise they can face electoral defeat.
People may have a vision of what a truly green building could be.
A submission for town planning may end up a watered down version – what is eventually delivered and maintained is often a pale comparison to the original vision.
People may desire more green, but they may not be willing to pay for the full extent of this if they do not believe the benefits will outweigh the costs.
As a result, there is a gap between the vision and the outcome.
This gap may be closed by articulating the full range of benefits that living architecture can provide in making our cities more resilient and liveable.
An economic model for living architecture
Economist Kim Whiteoak, senior consultant at RMCG, specialises in integrated water cycle management and was able to provide a model he developed for analysing the costs and benefits of water.
There are a number of similarities between water projects and greening cities in terms of how we can value and deliver them.
Whiteoak’s water model can be adapted to reflect the costs and benefits of living architecture.
Both greening and water management in our cities have costs and benefits that accrue to both private individuals and the general public, as well as the greater ecological good.
Some of the benefits are easily measured – economists call these ‘hard’ benefits – while some are not so easily measured and are thus termed ‘soft’ benefits.
This model sets out both the total costs and the total benefits of living architecture. It outlines how the costs – both capital expenditure and ongoing operational expenditure – can be offset by a series of benefits that layer one on top of the other. If enough benefits for both private and public can be accrued such that they approach parity with the costs, then the element can become economically justifiable.
The model includes both private and public benefits as well as hard and soft values. It also introduces some economic principles such as the community willingness to pay.
As part of the model, a short description of the predicament facing our cities in the face of increasing urbanisation will be set out, followed by a sketch of how living architecture can respond to this is provided.
The challenges we face in delivering living architecture in Australian cities will also be outlined, and the solutions that we have developed in meeting these challenges described.
Following this, a value proposition that describes the public and private benefits of green roofs, walls, and facades will be put forward.
Finally, all these concepts are illustrated with an economic model for living architecture that attempts to “Rebalance the Liveability Ledger.”
This paper provides decision makers including developers, governments, and designers a tool that will encourage and promote greener and more liveable Australian cities through the inclusion of green roofs, walls, and facades on more projects.
As our cities become increasingly larger and denser, the amount of green space per person is diminishing in inner urban areas.
Concrete, glass, and steel is impinging on our access to green and living things.
The impacts of climate change are also affecting the quality of our cities, with increasing numbers of hot days, more frequent and intense storms, and rising sea levels eroding our coast lines and waterfronts.
When associated with the pressures of urbanisation, these factors are conspiring to make our cities less liveable.
Governments are somewhat hamstrung. They have some influence through the planning legislation and development compliance requirements such ESD rating tools as well as public open space and storm water quality contributions. However, these alone are not sufficient to ensure significant improvements in improving our accessibility to greenery and green spaces.
It will take a combination of factors – both incentives and compliance legislation – to promote change.
We will need to take into account the future maintenance implications of these systems in terms of access, irrigation demand, and refurbishment.
This includes providing the clients and operations managers with realistic ongoing cost implications of the systems.
An economic model that supports the value proposition
It is not suggested that living architecture can or should be a substitute for on-ground green landscapes. Notwithstanding this, living architecture can provide benefits that contribute to making our cities more liveable.
No single benefit on its own will get a green roof, wall, or facade across the line.
However, if we can layer them together and outline both the private and public benefits, then they can combine to exceed the costs in the overall picture.
A lot of research has already been undertaken on these benefits and a lot more is still required.
Some of these benefits are tangible and can be directly measured such as energy savings or the offset costs for storm water treatment.
Soft values such as the benefit extracted from the enjoyment of tending a roof garden or the health benefit of reducing the urban heat island effect are more difficult to measure.
The private benefits of living architecture
Energy: A private benefit that can accrue from living architecture is the energy savings from mechanically cooling a building. We have modelled the thermal performance of a green roof in all of Australia’s climate zones and demonstrated that a green roof could reduce annual energy demand by more than 30 per cent when compared to a standard BCA compliant metal deck roof.
Real estate: It is well understood that properties associated with leafy green suburbs or those that overlook green spaces sell for more than those that do not. The same can be said for living architecture.
Research from the United States has shown increases in property values for a building with a green roof compared to one without.
This leads to a public benefit associated with property values: the increased revenue gained by government from higher land taxes and property rates as property values increase.
Marketing: There are marketing benefits associated with the public’s interest in environmentally friendly products and sustainability. Companies want to be seen to be green, which in return have financial benefits.
Productivity: Other private benefits include the increase in health and well-being associated with proximity to greenery. This both improves the productivity of employees and increases learning and overall heath which directly benefit people and organisations.
Food: There is also the opportunity that roof gardens can provide for food production.
The public benefits of living architecture
Urban heat island: Public benefits of greening cities include improvements in people’s health as a result of contact with nature and the cooling effect vegetation has on hot days.
As an example, in the Melbourne Metropolitan area, more people died from heat exhaustion on Black Saturday (February 7, 2009) than those that died as a direct result from the fires.
Storm water: Other public benefits of more greenery include improvements to the health of our waterways through the reduction in contaminants that enter them from polluted storm water runoff.
This is also a private benefit if storm water can be treated on site by a green roof.
Biodiversity: Then there is the overall improvement in biodiversity values as a result of more habitat being provided in our cities.
In a number of European cities, bee populations are rebounding due to the presence of green roofs, and endangered bird species are now no longer as threatened as they had been.
A value proposition for living architecture
It will take a combination of factors to get green roofs, walls, and facades implemented into more projects in Australia. These include overcoming the technical and design challenges in delivering them in our hot climates but also the financial and economic challenges that operate in the development industry.
An account will need to be made of the direct private incentives that can be provided, such as energy savings and reduced costs of managing storm water. As more research is published, developers and building owners will be increasingly able to include the direct benefits of green roofs, walls, and facades into their project costings.
In tandem with this, through the introduction of mandatory compliance and planning policy requirements that encourage and support green roofs, walls, and facades, we will see greater impetus to include them in more projects.
If an account of living architecture can include for both the hard and soft values that green roof, walls, and facades can provide, as well as the both the public and private benefits that accrue, then a good argument can be waged for the inclusion of these elements in many more projects in Australian cities.
The popularity of these elements is certainly gaining momentum. I hope an economic model that sets forth the overall value proposition will play a role in encouraging more widespread uptake of living architecture in Australia.