Finnish Museum of Natural History

Fifth Dimension – Green Roofs in Urban Areas

Helsinki University research group for sustainable green roofs



Green roof research rewarded
The Finnish Association of Architects rewarded the Fifth Dimension with 'TunnustusPAANU' for sustainable development on 3.3.2017.
Photo: Laura Hiisivuori

The Finnish Association of Landscape Industries, Viherympäristöliitto ry (VYL) rewarded the Fifth Dimension research programme with “the medal of the green year” thanks to the efficient production of new knowledge on green roofs. Susanna Lehvävirta, the leader of the programme received the prize in the House of the Estates in Helsinki on 27.10.2016.

Fifth Dimension group thanks so much and is happy for having such recognitions!

Topical issues also in the blog

The latest newsletter 1/2017 (released 23rd March 2017)


Why study green roofs?

Green roofs could essentially improve the living environment in cities, as they can be anticipated to produce regulating, provisioning and immaterial ecosystem services such as improvement of microclimate, balancing of hydrological cycle, CO2 sequestration, habitat provision, active cooling/insulation, dust filtering, opportunities for gardening and local food production in kitchen gardens, aesthetic improvement, additional green space and recreational services and educational services via e.g. nature paths on the roofs. The roof area increases substantially with urban development.

Experimental roofs (left): Helsinki, Jokimaa/Hollola, Oulu (Photos M.Gabrych)

Habitat creation is an issue that is pressing during this era of global change. As certain kinds of habitats are disappearing due to land use and climate change, or their combined effects, new kinds of habitats have to be investigated in order to save species from extinction. One option would be the green roofs that could be taken as parallel situations to some natural habitats. This habitat approach has several benefits as compared to mass production of any species that could survive on the roofs. Green roofs could offer complementary habitats for declining species and could be explicitly created to maintain desired services, for example pollination via supporting pollinators. Furthermore, mass production and use of unstudied species means a great risk of invasion (Heywood 2010), therefore it is imperative to carefully study the concepts, species and communities that will be used in the mass production of green roofs.

Storm water retention is a possibly important part of balancing the hydrological cycle in cities where the great proportion of impermeable manmade surfaces allows for serious run-off incidents and flooding during heavy rain. This problem is pressing as it is broadcasted that due to climate change, heavy showers will become increasingly frequent. Internationally, one of the drivers of city planning at the moment is storm water management.

The aesthetic and experiential services provided by the green roofs may include several perspectives raising several benefits. This so called “top landscape” can be viewed from the distance from the airplane, the “fifth facade” from buildings, and oblique roofs also from the ground level. In order to improve sustainability, our cities should be attractive for both living and spending free time, to avoid suburban sprawl and excessive travelling during weekends and holidays away from the cities.

THE FIFTH DIMENSION - GREEN ROOFS IN URBAN AREAS -research programme aims to produce high-level scientific and broadly applicable knowledge on optimal green roof solutions in Finland. Scientifically, green roofs serve as experimental model ecosystems for research and provide an opportunity for inter- and transdisciplinary research that is societally relevant. The research policy of the programme includes working in close contact with the end users of scientific knowledge, such as municipal and state authorities, companies and citizens. The main target of the programme concerns the potential of green roofs to enhance urban nature and ecosystem services, as part of multifunctional urban green infrastructure. The aim of the programme is to evaluate the various benefits green roofs may offer, and to develop optimal solutions and designs for green roofs that offer the best possible services for urban residents.


Our ongoing and past research themes include:

  • WATER - quality and retention
  • BIODIVERSITY - complementary habitats, indigenous species, invertebrates and plants
  • ECOLOGY - who colonises and survives, and why (roof size, isolation, substrate properties etc.)
  • LCA - life cycle of different green roof materials
  • REGULATION - policy instruments, legislation
  • SOCIOLOGY - images of the future (values and meanings related to green roofs), adoption of innovation
  • RECREATIONAL PSYCHOLOGY - restorative and multisensory aesthetic experiences on green roofs
  • ECONOMICS - cost-benefit analysis
  • URBAN PLANNING & GEOGRAPHY - role of green roofs in provisioning of ecosystem services, implementation in the city planning process
  • ARCHITECTURE  - how to implement scientific knowledge in real life cases

Experimental green roofs

POSTERS (Finnish/ English)
Ikano, Vantaa.pdf
Lare, Oulu.pdf
Exactum, Kumpula.pdf
Vuorikatu, Helsinki.pdf
Fabianinkatu, Helsinki.pdf
Lauttasaari sports center.pdf

Meilahti moss roof experiment
Lahti, Soilia
Lahti, Eliel

PHOTO GALLERY by Malgorzata Gabrych

Research group

Susanna Lehvävirta, group leader
Marja Mesimäki, user-perspective, adoption of green roofs, associate leader
Malgorzata Gabrych, vegetation, construction and stormwaters
Kukka Kyrö, invertebrates
Kirsi Kuoppamäki, stormwaters (quantity/ quality)
Marleena Hagner, substrate: biochar, mycorrhiza, micro-organisms
Kaisa Hauru, restorative and aesthetic experiences of visitors
Juhamatti Niemikapee, mosses
Long Xie, microbial interface of substrates
Johan Kotze, statistical analyses
Renan Benicke, outdoor spaces for children (Master's thesis, University of Münster)
Taina Suonio, policy instruments (Bachelor's & Master's theses)
Ville Vaurola, stormwaters/quality (Master's thesis, Uni Turku)
Elina Laurén (internship)

Following persons have been working/ participating in the group earlier:  Pasi Kallio, legal perspective, Väinö Nurmi, cost-benefit analysis, Sanaz Bozorg Chenani and Sini Veuro, life cycle analysis, Hanna Nieminen, adoption of green roofs in construction processes (Master's thesis), Alexandra Alfthan, vegetation on green roofs (Master's thesis), Laura Lehtovuori, green roof potential in Helsinki (Master's thesis), Tuuli Kassi, green roofs in architecture (Master's thesis, Aalto University), Minna Halonen, green roofs as habitats (Master's thesis), Orvokki Ihalainen, legal aspects (Master's thesis), Giulia Cappelletto, Master's thesis (University of Carrera, Italy), Niilo Tenkanen, green roofs in landscape architecture (Bachelor's thesis, Aalto University), Isabella Jeronimo, internship (Brazil), Jesse Grothe, internship (USA), Ferenc Vilisics invertebrates,  Anja Helena Liski, internship (University of Edinburgh), Niina Ala-Fossi and Noora Lehtovuori, photographing, videos.

Susanna Lehvävirta, Marja Mesimäki and Taina Suonio are board members of Scandinavian Green Roof Association.


  • Mesimäki Marja, Hauru Kaisa, Kotze Johan & Lehvävirta Susanna (2017). Neo-spaces for urban livability? Urbanites’ versatile mental images of green roofs in the Helsinki metropolitan area, Finland. Land Use Policy 61, 587 -  600. Published open access! See audio slides here or in YouTube
  • Kuoppamäki Kirsi & Lehvävirta Susanna (2016). Mitigating nutrient leaching from green roofs with biochar. Landscape and Urban Planning 152, 39-48.
  • Kuoppamäki Kirsi, Hagner Marleena, Lehvävirta Susanna & Setälä Heikki (2016). Biochar amendment in the green roof substrate affects runoff quality and quantity. Ecological Engineering 88, 1 - 9.

  • Mesimäki Marja & Nieminen Hanna and Lehvävirta Susanna (2015). Premises of realizing novel green infrastructure in construction processes – case green roofs. The Finnish Journal of Urban Studies. Finnish Society of Urban Planning. (only abstract available in English).

  • Gabrych Malgorzata, Kotze Johan & Lehvävirta Susanna (2016): Substrate depth and roof age strongly affect plant abundances on sedum-moss and meadow green roofs in Helsinki, Finland. Ecological Engineering 86, 95 - 104.

  • Bozorg Chenani Sanaz, Lehvävirta Susanna & Häkkinen Tarja (2015): Life cycle assessment of layers of green roofs. Journal of Cleaner Production 90, 153 - 162.

  • Kallio Pasi, Lehvävirta Susanna, Mesimäki Marja (2014). The multifunctionality of green roofs and the Finnish Land Use and Building Act. Finnish environmental law review 2/2014:98–138. (Available only in Finnish, english abstract)

  • Nurmi Väinö, Perrels Adriaan, Votsis Athanasios, Lehvävirta Susanna (2013): Cost-benefit analysis of green roofs in urban areas: case study in Helsinki. Report of Finnish Meteorological Institute 2013:2.

  • Páll-Gergely Barna, Kyrö Kukka, Lehvävirta Susanna & Vilisics Ferenc (2014): Green roofs provide habitat for the rare snail (Mollusca, Gastropoda) species Pseudotrichia rubiginosa and Succinella oblonga in Finland. Memoranda Soc. Fauna Flora Fennica 90: 13–15.

  • International Scientific Meeting for Green Roof Research 16.4.2012: MEMO (engl.) MEMO

In cooperation:

  • Väinö Nurmi, Athanasios Votsis, Adriaan Perrels and Susanna Lehvävirta (2016): Green Roof Cost-Benefit Analysis: Special Emphasis on Scenic Benefits. J. Benefit Cost Anal., 1–35.
  • Gerald Krebs, Kirsi Kuoppamäki, Teemu Kokkonen & Harri Koivusalo (2015): SIMULATION OF GREEN ROOF TEST BED RUNOFF. Hydrological Processes. (with Aalto-university)
  • Heating up Fifth Dimension & Dissertation Mikko Pervilä (Computer Science)
  • O’Toole ym. (2016): Current and future applications for biochar. Teoksessa Shackley, Ruysschaert, Zwart & Glaser (toim.) Biochar in European Soils and Agriculture – Science and Practice. Routledge, Taylor & Francis Group, s. 253 - 280. Chapter presents various applications of biochar. Kirsi Kuoppamäki from our research group participated in writing this chapter by telling about the use of of biochar in green roofs.
  • Faehnle, Söderman, Schulman, Lehvävirta (2015). Scale-sensitive integration of ecosystem services in urban planning. Geojournal 80:411-425.

Theses (examples)

Related research
Kaisa Hauru, 2015: Eco-experiential quality of urban forests: combining ecological, restorative and aesthetic perspectives, Academic Dissertation


University of Helsinki
Kone Foundation
Nessling Foundation
EU Horizon 2020 ThinkNature
Helsinki University Centre for Environment, HENVI
Enhancing Sustainable Urban Development through Ecosystem Services - ENSURE
Uusimaa Regional Council
Helsinki Metropolitan Region Urban Research Program
City of Vantaa
Maiju and Yrjö Rikala Foundation
Real Estate Foundation Kiinko
Kansainvälinen designsäätiö


It's cool - it's floral (HUB)

Green Roofs Tree of Knowledge
Urban habitats: Green Roofs and Biodiversity
Niemelä et at.: Urban Ecology - Patterns Processes and Applications

Experimental green roof flourishing in Hollola, on the roof of our cooperation partner Rakennusbetoni- ja Elementti Oy (photo: Kirsi Kuoppamäki 2015)


Person in charge of the page: 
Green roof research group