Biodiversity and Green Roofs

A three-year PhD study based at Royal Holloway, University of London and linked and interacting with a similar project in Switzerland, at the University of Wadenswil.

The Background:

To date the only full study on green roofs and biodiversity in Europe has been undertaken in Switzerland. In 2002 two small studies were undertaken in London on invertebrates and green roofs. One, an MSc study, undertaken by G. Kadas who will be undertaking this study, provides the basis of this project.

G. Kadas Published Scientific Papers

http://www.urbanhabitats.org/v04n01/invertebrates_full.html
http://www.iob.org/userfiles/File/biologist_archive/Biol_52_3_Kadas.pdf

Biodiversity and Green roofs is a key issue for the London Biodiversity Partnership [LBP] especially in regard seeking mitigation for the loss of brownfield land and its biodiversity interest. This project addresses in part a key action for the London Biodiversity Partnership’s Black Redstart Action Plan [BRAP] [www.lbp.org.co.uk], as green roofs as mitigation for brownfield land is a key issue for the BRAP:

• Objective: To promote good practice where development is liable to impact on populations

• Action: Determine habitat requirements in Urban areas through collation of current information and new research.

It also addresses a key recommendation in English Nature’s forthcoming report on green roofs:

• Further case studies of existing green roofs, to determine what species utilize what types of roofs

• Studies of patterns of colonization and succession on green roofs of different types over a number of years and, coupled with this, the effects different management strategies

• Experimentation with different design, orientations, substrate type and depth and micro-topographical detailing

• Examination of whether connectivity to the ground is important, for example through climber cover walls, vegetated buttresses or ramps

The Project:

Aims

• Provide detailed information on the biodiversity of green roofs to ensure that such roof systems advocated in the Mayor’s Energy, Water and Biodiversity Strategies are maximized for biodiversity.
  
  
• To provide in detailed information on prices of green roof installation in a range of building types and development zones and maintenance costs
  
  
• To support and provide advice to professionals [architects, developers, planners and ecological consultants] involved in regeneration and development on how green roofs are a solution in regard urban green space; and provide design details.
  
  
• In partnership with the LBP and BRAP set up a network and website to broadcast findings.
  
  
• Condensed report on an annual basis of the findings re development cost implications of green roofs
  
  

Activity

• Study a number of current green roofs and artificial habitats associated with brownfield land to assess and evaluate the potential of green roofs as mitigation within urban development programmes.
  
  
• Study will focus on invertebrates [the Thames Gateway is home to 22 Red Data/Nationally Scarce species]. The research will target certain groups of importance the UK biodiversity action plan and English Nature’s Species Recovery Programme, notably, beetles, spiders and bees [Hymenopterans]
  
  
• The project will research the costs of green roofs for a various building types and the on going cost in terms of maintenance
  
  
• Liaise with sister project in Switzerland.
  
  
• Install trial sample trays on existent developments in partnership with the BRAP
  
  
• Identify key factors affecting the biodiversity on roofs.
  
  
• Identify design factors on roofs to ensure they are maximized for biodiversity
  
  

Progress

In 2004 two field laboratories have been installed. These consist of 180m² divided into 45x 2m by 2m plots.

Livingroofs.org would like to gratefully acknowledge the financial support provided by English Nature, The People's Trust for Endangered Species and Alumasc Exteriors in support of the installation and maintenance of these laboratories.

A larger photogallery of the installation at Canary Wharf is available to view here.

Green roof laboratory installation at Canary Wharf

London Zoo green roof laboratory

Monitoring of brownfield sites and other green roofs continues

Ongoing

Creekside Roof – a custom made ‘brown’ roof consisting of crushed concrete. Very slow to colonise due to arid conditions

Creekside Ground – Landscape of crushed concrete and brick

 

Sentinels Wharf – top of flood defence specially designed as a brownfield habitat

Crown Wharf – small piece of land as mitigation for black redstarts

Wood Wharf – one of the last remaining brown sites in the Isle of Dogs soon to be developed by British Waterways [PhD sponsor]. The development is to include green roofs for biodiversity. www.woodwharf.com

Laban Dance Centre – the first ‘brown’ roof. A mixture of site substrates which is beginning to colonise

Canary Wharf x3 – three sedum mat roofs in the Canary Wharf Estate www.canarywharfgroup.com

New Providence Wharf – a sedum plug planted roof installed as mitigation for black redstarts

Royal Holloway College – a sedum plug planted roof installed in spring 2004

Grays Inn Road - Time Lapse Movie of installation [opens in new window]

For further information contact research @ livingroofs. org