WORLD GREEN INFRASTRUCTURE AWARD
Hort Innovation Green Roof Research Project 16002
Category:
GREEN INFRASTRUCTURE RESEARCH AND ACADEMIC WORK
Project creators
Australia
Country
Melbourne
City
University of Melbourne
Institution
PostDoc
Nominator Degree Program
Nicholas Williams
Nominator
Project specifications
Research includes physical testing
or observation location
Location City(s)
Main location Country
Other countries list
YES
Melbourne
Australia
N/A
Project Abstract
Originality Declaration
Consent for Use of Materials
Green roof construction in Australia is proceeding relatively slowly compared to other countries, despite a decade of the research demonstrating their local benefits and functions. This indicates that substantial barriers to green roof implementation remain. Consequently, the overarching objective of our four year $1.1 M Hort Innovation research project nominated for this award was to better understand and overcome some of the fundamental economic, design, social and horticultural barriers to greater green roof construction in Australia. Project results were communicated in scientific papers detailing literature reviews and experimental studies and industry guidelines including the Maintenance Guidelines for Australian Green Roofs and Australia’s first Green Roof Planting Guide and a Roadmap for Green Roofs, Walls and Facades in Australia’s Urban Landscapes 2020-2030 which is already generating positive change in the Australian green roof sector including the creation of a new industry
All of the research is original
We consent to the use of the information in this application and the materials uploaded. However, permission may be required from the publishers of the journal papers.
Research details
Breef research description
Australia
Source of funding
Australia
The Research type
The Research relates to
Source of funding
Other
other
national research grant
Year of construction
Year of research completion
Area brutto (m2)
2018
2022
Research outcomes
Is the research a precursor to expected follow up research?
Our findings have already stimulated additional research into green roof designs that support biodiversity and a project to develop lower cost green roofs for the Australian market. For the latter project, trials are currently being undertaken with the support of the City of Melbourne and Victorian Department of Environment and Climate Change Action on the 1 Treasury Place office building in Melbourne’s CBD. This is a high profile project as the building includes offices of the Victorian premier and treasury staff.
How does the research address the issue of water stewardship?
Workstream 2 research identified plant species that require little or no irrigation thus supporting water stewardship. We investigated the effect of three substrate depths (10, 15 and 20 cm) on plant survival and condition for 75 native and exotic plants grown on Australian or Mediterranean green roofs over a 16-month period on the Burnley Research Green Roof. We took a functional group and survival analysis approach, looking at the relationship between leaf traits and plant type on plant performance and survival, and correlating this with substrate depth, substrate moisture and temperature and rainfall. The trial finished with a water deficit and heat experiment where supplementary irrigation was turned off over summer (2021-22) and plants were subject to extreme heat. Results will be published in an upcoming scientific paper but have also been included in a section of the Burnley Green Roof Planting Guide titled Plant Selection for green roofs designed for stormwater management.
How does the research address the human well-being aspects of GI?
The research included a literature review of how green roofs improve well-being. It revealed a complexity of experiences on green roofs and the circumstances when they may provide psychological benefits. While grassy and flowering green roofs are most likely to support positive aesthetic and restorative outcomes, this is unlikely to occur without consideration of plant survival, impact of roof top heat and wind on human comfort, perceived access to the roof, design fit with social norms for nature in cities, and provision for restorative activities and individual adaptation of the site. We also investigated what features create fascinating green roofs which are more likely to be restorative. These were natural and built features on the roof that increase complexity through space and time, create movement on the roof, encourage multi-sensory engagement and connect people with distance through vast vistas. Results have important practical implications for green roof design.
How does the research address the economic aspects of GI?
The literature review at the commencement of the project identified uncertainty about the costs of green roof maintenance as one of the major economic barriers to green roof construction in Australia. To reduce these Workstream 3 reviewed existing green roof reports and guidelines, in Australia and internationally; and researched green roofs maintenance, synthesizing knowledge from academic and industry sources. To upskill green roof contractors and reduce costs to building owners wanting to install green roofs, the results were compiled into the “Maintenance Guidelines for Australian Green Roofs” the development of which was supported by the creation of an industry reference group.
How does the research address the environmental sustainability aspects of GI?
As the objective of the project was to better understand and overcome some of the fundamental barriers to greater green roof construction in Australia, the project inherently addresses environmental sustainability of Australian cities. In particular the research output Roadmap for Green Roofs, Walls and Facades in Australia’s Urban Landscapes 2020-2030 provides an industry generated plan to increase the sustainability of Australian cities through extensive and rapid uptake of green roofs and walls.
How does the research address social aspects of GI?
For Workstream 1, we ran 2 highly successful industry workshops in Sydney and Melbourne to create a vision, and identify pathways, for greater greening. These brought together researchers and over 60 green roof industry practitioners We used an Appreciative Inquiry approach, (Cooperrider & Srivastva, 1987) a form of action research with a theory of collective change for “organising a method for changing social systems” (Bushe, 1999). It explicitly affirms and develops positive images that people hold and harnesses them to provide a method for transforming an entire system (Bushe, 1999). This is critical in diverse sectors such as green roofs where multi-actor and multi-organisational collaborations are required. We asked participants to collectively create a vision of these future green cities and understand the role of collaborative networks in fostering adoption and sector growth. Research outputs include a scientific paper and industry Roadmap for Green Roofs, Walls and Facades.
How does the research address the topic of biodiversity?
One aim of the project was to develop new plant palettes for different green roof build-ups thereby increasing the diversity of species used. To do this we • investigated the suitability of Australian annual species by evaluating how irrigation frequency affects plant cover, species abundance, richness and diversity, plant traits and functional diversity of a 16 species seed mixture of Australian annual species. • Wrote the Burnley Green Roof Guide. It includes more than 150 species proven to be successful on green roofs through plant trials in this project, and from ten years of quantitative and qualitative data generated from the three green roofs at the Burnley campus and research projects undertaken by the Green Infrastructure Research Group. Through this project we have developed recommended plant palettes for five common green roof typologies for southern Australian conditions including a green roof to support fauna biodiversity.
What types of GI multifuncionality are addressed by the nominated research?
The research project explicitly addressed the multiple functions of green roofs including biodiversity, human well-being and water stewardship – see below. Further the guides produced as an output summarise our results and provide advice to the green roof industry about how to design and maintain green roofs for multifunctionality.
Does the research support innovation?
The research supports innovation in numerous ways including: • Undertaking ground-breaking research that uncovered greens roof features that best promote human well-being (Williams et al 2019, Lee et al 2022) • Providing research-based evidence to encourage a greater diversity of plants in Australian green roof designs. • Writing the first Australian specific green roof planting guide as a project output. It provides specific plant palette recommendations for green roofs designed for particular functions – i.e. biodiversity, human well-being (Rayner et al 2023) • For the first time developing a collective understanding within the Australian green infrastructure sector of the actions is required to advance green roofs and walls (Lee et al 2022; Williams et al 2021, Bathgate et al 2022) Our research is also innovative in its approach. It explicitly involved the green roof industry to co-design the research program and they contributed to reports, guides and Industry Roadmap.
Project video
Documents
Public vote
You can participate in the public vote. Make sure you read the voting conditions. Confirm that you are not a robot to use the vote button.