Growing greener cities

Who doesn’t want their house, apartment or office to be – literally – greener?

Green walls (or vertical gardens) and roofs were once seen as just a yuppie fad – a novel building addition that might get you a few extra points for your outdoor area on The Block or bragging rights on your latest five star green building.

But as developers and the public recognise the environmental, health, and economic benefits, and urban planners look for new ways to increase green space in our increasingly over-developed city centres, green infrastructure is going mainstream.

Many people see the benefits and long for a piece of the action, but get stuck at the first hurdle. Where do I start? What plants should I grow? How do I water this thing?

University of Melbourne researchers worked with government and industry groups to produce the Growing Green Guide, which is giving people the tools they need to incorporate green infrastructure into their buildings.

The Guide has just been awarded a 2015 Premier’s Sustainability Award in the Education category.

Building a beautiful, functional, low maintenance, sustainable and enduring green wall or roof is hard. Researchers working at the University of Melbourne’s Burnley campus have spent years studying the ideal combinations of plants, substrates and irrigation materials for green roofs, and put these into practice through real projects across the city.

Mr John Rayner and Dr Susan Murphy, green infrastructure researchers and horticulture lecturers in the School of Ecosystem and Forest Sciences, University of Melbourne, say cities are losing vegetation cover as population density increases.

“In the City of Melbourne, for example, between 1988 and 2009 vegetation cover decreased from 24.6 per cent to 13.6 per cent,” Dr Murphy says.

Mr Rayner says the aim of the Growing Green Guide is to reverse this trend, and start increasing the amount of green space in cities.

It’s such a difficult field to negotiate. So we thought it would be useful to have a local guide that covers design, construction and maintenance of green infrastructure.

In 2011 Mr Rayner teamed up with Ms Gail Hall, Coordinator, Green Infrastructure for the City of Melbourne to develop guidelines for green roofs, walls and facades across Melbourne. With the City of Port Phillip as an early partner and later the Inner Melbourne Action Plan (a collaboration between the cities of Melbourne, Port Phillip, Stonington, Yarra and Maribyrnong), funding was obtained from the Victorian Adaptation and Sustainability Partnership ( State Government of Victoria).

Project Officer Ms Julie Francis and University of Melbourne Research Officer Dr Susan Murphy then spent the next two years writing and developing the guide, with support from two active industry reference groups.

Published in February 2014, the Growing Green Guide has since been downloaded more than 70,000 times. It has also been incorporated into council guidelines for sustainable city living, is used widely as an education and learning resource, has been translated into both Chinese and Spanish, and inspired and facilitated increasing numbers of public and private green infrastructure projects.

Mr Rayner says the green roof industry is still in its infancy, and in the past was fragmented and struggling for legitimacy, but the guide has galvanised the industry.

“People regularly use it as a reference source for projects. They use it as a reference for their clients and champion its use in the building industry,” he said.

“A developer or an architect, say, might have an idea of what the thing might look like, but not what maintenance might be required.”

Phil Edwards runs a ‘living architecture’ company called Coolth.inc that specialises in vertical gardens and green roofs, and was one of the contributors to the guide.

“I use it quite regularly – I actually keep a copy by my bedside,” he laughs.

I’m often designing or quoting on systems I haven’t used before. The guide gives me a wealth of experience that I couldn’t get anywhere else.

Mr Edwards says every project is different. He might work on a vertical garden with sun exposure he hasn’t come across, or a wall material he is unfamiliar with. He uses the industry case studies in the guide to look for similar experiences, which helps with things like plant selection and costing.

“For a young industry, there are no experts, there’s no one individual who has all the experience,” he says.

“The guide makes up for a lack of industry experience and longevity.”

Owner-builder David McMillan is in the final stages of planning for a bungalow with a green roof he plans to build in his backyard over the next 12 months.

We’ve used the Growing Green Guide pretty extensively – for plant selection, as a guide to materials, for weight loadings and for costing.

While designing his green roof, Mr McMillan visited several sites used as case studies in the guide, as well as twice touring the Burnley Green Roof at the University of Melbourne.

The guide is freely available for anyone to use, rework, republish and translate, and so green infrastructure designers can incorporate parts of the guide into information for their clients or customers.

An industry reference group advised on the progress of the guide, and Mr Rayner says their early involvement has led to better engagement and use of the product.

“A highlight for me is seeing that our research is leading a lot of the discussion around green roofs in Melbourne,” he said.

The Growing Green Guide won the Australian Institute of Landscape Architects Research and Communication Award and was a finalist in the Victorian Adaptation & Sustainability Partner Award, and the prestigious Victorian Premier’s Sustainability Award for Education.

Mr Rayner and colleague Dr Murphy hope the Growing Green Guide becomes a living resource, with a website that is regularly updated with the latest research and insights.

There is newer and better research around water issues, plant choice and substrates being produced, and I’d love to see architects, developers, designers move towards a common understanding about what works and what doesn’t.