Green Area Factor tool for districts

The multiple benefits of urban green areas calculated using the Green Area Factor tool for districts. Credit: Mette Hiltunen


The Green Area Factor (GAF) is a practical tool for city planners based on research data that considers local characteristics and does not discriminate against low-budget projects by favouring expensive ecological solutions. The tool helps cities to increase the share and effectiveness of green areas. GAF for districts is a new approach that focuses on a specific area rather than provide a general overview. The tool has been piloted a number of times in Helsinki at the district level (Kyläsaari 2020, Malmi 2021), where lessons were learned to improve the methodology. The aim is to understand the experience drawn from the pilots and identify the preconditions for scale-up to use at the district level. The vision of the method is to develop a Helsinki-specific, easy and digitalised green factor tool for integrating more ecological data into urban planning.  

Description of practice 


1. Current use and experience: The first phase consisted of user experience from the pilots and understanding the pivotal development needs using questionnaires and a workshop. Two surveys were conducted – one for experts and another for participants who work for the City of Helsinki. 

2. Integration into existing operating models: In the second phase, workshops and interviews were conducted to analyse existing land use planning processes to find the correct point for applying the new method. Resources and responsibilities for the development work were also discussed. 

3.  Digitalisation: In the third phase of the project, the preconditions for automating and digitalisation were analysed in a workshop.  

Who was involved  

Urban planners, architects from Kalasatama team, B. Green, team leaders in landscape planning at the City of Helsinki, team leaders/unit directors at the City of Helsinki Urban Environment Division, a professional 3D+ team (in the second workshop) and three consultants from WSP Finland.  

Promotion and communication 

● The project was promoted through a contact person at the City of Helsinki, who helped with finding the right people to participate. 

● A webinar was conducted for 80 participants, comprising the people involved, as well as urban planners and architects from other municipalities. A recording of the webinar is available online. 


Skills: The project required the involvement of urban planners, architects and people with knowledge and skills in various environmental aspects.

Resources: Workshops were held using MS Teams and the Miro collaboration tool. The survey was carried out by consultation firm WSP Finland. B. Green provided funding for the project.  

Time commitment 

The project took place over 3–4 months in the summer holidays: one month each for the interviews and workshops, and one month to compile the results. 


Level of participation
  • No participation (stakeholders/citizens were not included) 
  • Informing (informing citizens about what is planned) 
  • Consultation (offering options and listening to the feedback) 
  • Co-production in some of the aspects 
  • Co-production from start to end 
Urban planning challenge(s) tackled Governance and institutional factors

  • Working collaboratively
  • Standards and regulatory processes
  • Finance

Stakeholder engagement 

  • Public acceptance
  • Shared decision-making 
  • Social inclusion

Knowledge and skills

  • Awareness and communication
  • Expertise
  • Technical integration

Lessons learned

● Some of the workload can be outsourced. This requires standardisation and good guidance.

● Workshops are a great way to bring different expertise to a project, although the project would have benefited from having more people in the workshops.

● Co-production of information was seen as a success factor.

● At present, the method only covers public areas, not plots. However, natural processes function regardless of administrative borders.

● It is important to promote the tool in Helsinki to show what could be done in the city.

● The most efficient timing for use of the tool was identified as before or at the detailed planning stage. However, ecosystem information can be used at different stages throughout the process.  


● The tool is now being used by different actors. It is Helsinki-specific, which makes argumentation, assessment and comparison possible.

● The tool can be used to identify and promote the best solutions for urban structures, and to test and enhance a plan.

● An important outcome is the promotion of understanding of the value of green infrastructure and the complex chains of interaction in nature.

● Currently, the best procedure for using the tool is to compare different plan versions or scenarios against each other and the present the situation in a single design area; there is no need for general target values.

● The green area factor can be valuable at different levels: for analysis, planning and impact assessment.  

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