Bratislava, Slovakia
City population: 410016
Duration: 2017 – 2017
Implementation status: Completed
Scale: Sub-microscale: Street scale (including buildings)
Project area: 1400 m2
Type of area: Building
Last updated: October 2021

This NBS site is part of the Bratislava Zelenaj Project. This particular NBS involves the creation of vegetation on buildings as a means to mitigate the effects of climate change in cities due to urban overheating caused by global warming. It targets the residents of the Archa House of Seniors (Domove seniorov Archa) in Bratislava as part of the citywide project “Bratislava is preparing for climate change” with the aim of protecting and promoting the welfare of the city’s vulnerable citizens from climate change effects. The roof's main function is buffering the discharge of excess rainwater. (10)

Bratislava Zalenajsa


Nature-based solution

  • Nature on buildings
  • Green roofs
  • Green areas for water management
  • Sustainable urban drainage systems

Key challenges

  • Climate action for adaptation, resilience and mitigation (SDG 13)
  • Climate change adaptation
  • Water management (SDG 6)
  • Stormwater and rainfall management and storage
  • Green space, habitats and biodiversity (SDG 15)
  • Green space creation and/or management
  • Environmental quality
  • Air quality improvement
  • Noise reduction
  • Regeneration, land-use and urban development
  • Regulation of built environment
  • Health and well-being (SDG 3)
  • Improving mental health
  • Improving physical health


Creation of new green areas

Project objectives

- The main goal is to discharge excess rainwater. - Protection of vulnerable people against urban overheating (especially senior individuals). - Relaxing and recreational space overlooking the local Kramare area. - Evaporation of water from the vegetation layer ought to provide the building with a cooling effect in the summer. - Generally reflects sunlight energy for photosynthesis, helps accumulate water retention, improves air quality, and absorbs dust, pollutants and noise suppression - Broadly addressing the effects of climate change at a micro-climate level (summer heat, prolonged droughts and conversely increasing torrential rains). (10)

Implementation activities

1400 square meters of green roof was installed.

Climate-focused activities

Climate change adaptation:

  • Increase or improve urban vegetation cover to help reduce outdoor temperature
  • Implement green walls or roofs to lower indoor temperature and provide insulation
  • Create or improve outdoor spaces to help people escape from urban heat

Main beneficiaries

  • Citizens or community groups
  • Marginalized groups: Elderly people


Management set-up

  • Co-governance with government and non-government actors

Type of initiating organisation

  • Local government/municipality

Participatory approaches/ community involvement

  • Unknown

Details on the roles of the organisations involved in the project

Bratislava City Office provides overall coordination of the project named "Bratislava is preparing for climate change - pilot application of the measures in the field of sustainable rainwater", along with relevant subsidiary city districts for specific interventions. The relevant district for this intervention is Nové Mesto. Cooperation on the project was also sought with the Bratislava Regional Conservation Association, Bratislava Water Company, City Committee of Slovak Nature and Landscape Conservation Union, City Forest in Bratislava, Comenius University in Bratislava, Nature Sciences Faculty to involve them in the plans. The Norwegian partner COWI was involved because of its experience in the field and to underline the spirit of the EEA Grants and Norway Grants regarding international cooperation. (2)

Project implemented in response to ...

... an EU policy or strategy? Unknown
... a national policy or strategy? Unknown
... a local policy or strategy? Yes (The NBS is as part of the project ‘Bratislava is preparing for climate change’ a practical contribution to the implementation of the City of Bratislava's prepared and approved Adaptation Action Plan. (2, 8, 9, 13, 14))


Total cost

€100,000 - €500,000

Source(s) of funding

  • Public local authority budget
  • Other

Type of funding

  • Earmarked public budget
  • Direct funding or subsidy

Non-financial contribution

Type of non-financial contribution
  • Provision of labour
Who provided the non-financial contribution?
  • Private sector (businesses, financial institution)

Impacts and Monitoring

Environmental impacts

  • Climate, energy and emissions
  • Lowered local temperature
  • Environmental quality
  • Reduced noise exposure
  • Water management and blue areas
  • Improved stormwater management
  • Green space and habitat
  • Increased green space area
  • Increased number of species present

Economic impacts

  • Reduce financial cost for urban management

Socio-cultural impacts

  • Social justice and cohesion
  • Improved liveability
  • Improved access to urban green space
  • Health and wellbeing
  • Improved physical health
  • Improved mental health
  • Other

Type of reported impacts

Achieved impacts

Presence of formal monitoring system


Presence of indicators used in reporting

No evidence in public records

Presence of monitoring/ evaluation reports

No evidence in public records

Availability of a web-based monitoring tool

No evidence in public records