1. General information
Location and description of the intervention
City or FUA
Hannover
Region
Europe
Native title of the NBS intervention
Begrüntes Hannover
Short description of the intervention
The project "Sustainable Support Program for Greening Buildings and Minimizing the use of space using the example of Hanover" was established jointly by BUND (Bund für Umwelt und Naturschutz Deutschland) and the state capital of Hanover. The goal of the project is to transform as many barren house walls and dull grey roofs and asphalted areas into green oases throughout the city. Since May 2013, all house and landowners, housing associations and building communities have been able to apply to the BUND for a subsidy for green roofs and facades. On 2017, the project was expanded to include unsealing of areas like inner courtyards, driveways, etc, thus creating new green areas. Advice on the correct greening measures and on professional unsealing have been also offered by BUND.
The project is funded by the state capital of Hanover, the German Federal Environmental Foundation (DBU), the Sparkasse Hannover and by proKlima. The "Green Hanover" funding program will end on December 31, 2020. (Reference 1)
Address

Germany

Location
The NBS is a city-wide initiative, the GIS point marks the centre of the city
Type of area before implementation of the NBS
Residential
Building
Other
Please specify “other type of area” before implementation of the NBS
Sealed surfaces like inner courtyards
Website of the intervention
https://www.hannover.de/Leben-in-der-Region-Hannover/Umwelt-Nachhaltigkeit/Natu…
Timeline of intervention
Start date of the intervention (planning process)
unknown
Start date of intervention (implementation process)
2012
End date of the intervention
2020
Present stage of the intervention
Ongoing
Goals of the intervention
The main goal of the intervention is to transform as many bare houses walls, dreary gray roofs and asphalted areas into green oases throughout the city (Ref. 1).
The specific objectives of this project are as follows:
1) Providing green habitat for species in the city; 2) Aiding in urban water storage and air quality; 3) Having temperature-compensating effect and preventing the summer heating of the buildings; 4) Preserving and increasing biodiversity; 5) Contributing to the well-being of the inhabitants (Ref. 1,2).
Quantitative targets
Unknown
Monitoring indicators defined
Increase in greenery in the city; Reduction of heat island effect; (1)
Sustainability challenge(s) addressed
Climate action for adaptation, resilience and mitigation (SDG 13)
Climate change adaptation
Water management (SDG 6)
Flood protection
Stormwater and rainfall management and storage
Green space, habitats and biodiversity (SDG 15)
Habitat and biodiversity conservation
Green space creation and/or management
Environmental quality
Air quality improvement
Noise reduction
Regeneration, land-use and urban development
Regulation of built environment
Promote natural styles of landscape design for urban development
Inclusive and effective governance (SDG 16)
Inclusive governance
Effective management
Social justice, cohesion and equity (SDG 10)
Social cohesion
Social interaction
Health and well-being (SDG 3)
Improving mental health
Improving physical health
Climate change adaptation: What were the goals of the NBS?
Reduce exposure to climate risks directly
Reduce the impacts of climate risks events on urban places and communities
Build resilience
Climate change adaptation: What activities are implemented to realize the conservation goals and targets?
Increase or improve urban vegetation cover to help reduce outdoor temperature
Implement green walls or roofs to lower indoor temperature and provide insulation
Habitats and biodiversity conservation: What types of conservation goals are / were defined for the NBS intervention?
Ecosystem-focused
Habitats and biodiversity conservation: What activities are implemented to realize the conservation goals and targets?
Protect and enhance urban habitats
Create new habitats
Preserve and strengthen habitat connectivity
Means for conservation governance
Manage biological resources for conservation and sustainable use
Raise public awareness
Public engagement
Create and use scientific knowledge for conservation
Capacity building
Implementation activities
Greening of façades and roofs with eligible measures for small buildings such as houses, garages or carports, as well as commercial buildings such as offices, factories and storage halls.(Reference 1)
-Support program for green roofs and facades: This funding offer has been available in Hanover since mid-2012 and has so far been successfully accepted so that over 10,000 square meters of roof areas and various facades have already been planted.
-Support program for unsealing: With the expansion of the program to include the aspect of unsettling, a new greening offensive has started in the city since 2017. For unsealing measures in the state capital Hanover provides financial grant. (Reference 2)
- Unsealing of areas like courtyards, driveways, etc to increase green areas
Type of NBS project
Creation of new green areas
Strategy, plan or policy development
Improved governance of green or blue areas
Please specify other type of green wall
Unknown
NBS domain and interventions
Ecological domain(s) where the NBS intervention(s) is/are implemented
Nature on buildings (external)
Green roofs
Green walls or facades
Grey infrastructure featuring greens
Other
Please specify "other external building green"
unsealing of unnecessary
Please specify "other urban green space connected to grey infrastructure"
Unsealing of unnecessary infrastructures like courtyards, driveways, etc
Type of Green Wall
Climbing façades
Other
Please specify other type of green roof
Unknown
Type of Green Roof
Other
Vegetation Type
Grass
Shrubs
Other
Amenities offered by the NBS
Unknown
Services
Expected ecosystem services delivered
Regulating services
Local climate regulation (temperature reduction)
Air quality regulation
Noise reduction
Flood regulation
Pollination
Mediation of smell / noise / visual impacts
Habitat and supporting services
Habitats for species
Maintenance of genetic diversity
Cultural services
Aesthetic appreciation
Mental and physical health and wellbeing
Intellectual interactions (scientific and / or educational)
Physical and experiential interactions with plants and animals
Social and community interactions
Scale
Spatial scale
Meso-scale: Regional, metropolitan and urban level
Sub-microscale: Street scale (including buildings)
Beneficiaries
Primary Beneficiaries
Citizens or community groups
Governance
Governance arrangements
Co-governance with government and non-government actors
Non-government actors
Non-governmental organisation (NGO) / Civil society / Churches
Citizens or community groups
Please specify the roles of the specific government and non-government actor groups involved in the initiative
The project was implemented by the city of Hannover in cooperation with the BUND Region Hannover (NGO) and it is directed to different citizens' groups who are eligible to apply for funding.(Reference 2)
Key actors - initiating organization
Local government/municipality
Non-government organisation/civil society
Key actors - Other stakeholders involved (besides initiating actors)
Local government/municipality
Non-government organisation/civil society
Citizens or community group
Participatory methods/forms of community involvement used
Co-planning (e.g. stakeholder workshops, focus groups, participatory mapping)
Dissemination of information and education
Consultation (e.g. workshop, surveys, community meetings, town halls)
Joint implementation (e.g. tree planting)
Policy drivers
NBS intervention implemented in response to an Regional Directive/Strategy
Unknown
NBS intervention implemented in response to a national regulations/strategy/plan
Unknown
NBS intervention implemented in response to a local regulation/strategy/plan
Yes
Please specify the "local regulation/strategy/plan"
In response to the "Sustainable Support Program for Building Greening and Minimizing the Use of Land Use in Hannover".(1)
The current project is a continuation of "Innovative Open-End Security Concept for the Development of Green Urban Neighborhoods".(2)
Mandatory or voluntary intervention
Unknown
Enablers
Presence of specific city-level GI/NBS vision/strategy/plan - mentioned in connection to the project
Yes
Please specify
The project is also in line with the 'More nature in the city' ("Mehr Natur in der Stadt") plan. ( Reference 3)
Presence of specific city-level GI/NBS section/part in a more general plan - mentioned in connection to the project
Unknown
Please specify the general plan with GI/NBS section
In response to the "Sustainable Support Program for Building Greening and Minimizing the Use of Land Use in Hannover".(1)
The current project is a continuation of "Innovative Open-End Security Concept for the Development of Green Urban Neighborhoods".(2)
If there is a relevant strategy or plan, please specify the theme / type of the plan.
City specific green space strategy or plan
Urban redevelopment plan
Please specify other vegetation type
Climbing plants
Presence of city network or regional partnerships focused on NBS - mentioned in connection to the project
Yes
Please specify
The new funding program was initiated by the German Federal Environment Agency (BUND), the Kreisgruppe Region Hannover, the German Federal Foundation for the Environment (DBU) and the Department of Environment and City of the City of Hanover.(Reference 1)
Presence of GI / NBS research project - mentioned in connection to the project
Unknown
Subsidies/investment for GI / NBS in the city - mentioned in connection to the project
Yes
Please specify
Since May 2, 2013, all house owners, housing cooperatives and construction companies can apply for a subsidy for roofing and facade greening at BUND.
This funding is possible thanks to financial support from the city of Hanover, the German Federal Foundation for the Environment (DBU) and Sparkasse Hannover.( Reference 1)
Co-finance for NBS
Yes
Co-financing governance arrangements
Unknown
Was this co-governance arrangement already in place, or was it set up specifically for this NBS?
Unknown
Financing
Total cost
Unknown
What is/was the Cost/Budget (EUR) of the NBS or green infrastructure elements?
unknown
What are the total amount of expected annual maintenance costs?
unknown
What is the expected annual maintenance costs of the NBS or GI elements?
unknown
Please specify cost savings
unknown
Please specify total cost (EUR)
The funding available within the project's framework: up to 3500 EUR for projects that aim at the greening of the facades and up to 10 000 EUR for roof greening and unsealing projects - depending on the size.(Reference 1) No data available on how many funds have been spent so far.

Source(s) of funding
Public local authority budget
Funds provided by non-governmental organization (NGO)
Other
Please specify other source of funding
Funds provided by Sparkasse Hannover - not a corporate investment though.
Type of fund(s) used
Earmarked public budget
Direct funding (grants, subsidies, or self-financed projects by private entities)
Non-financial contribution
Unknown
Business models
Risk reduction model
Which of the involved actors was motivated by this model?
Public actor (e.g. municipality)
Private non-for-profit actor (e.g. NGO, foundation)
Type of innovation
Social
Economic innovation
Please specify social innovation
A new funding program for roof and facade greening in the city of Hanover.(1) As the project description states the various approaches are brought together in a project with the help of an innovative funding program that is accessible to all residents.(2)
Novelty level of the innovation
The innovation is copied/derived from previous initiative(s) without substantial adaptation
Please specify novelty level of the innovation
Under the motto "Greenery Hanover", the joint project "Sustainable Support Program for Building Greening and Minimization of Land Use" was launched in April 2017 by the city of Hanover in cooperation with the BUND Region Hannover. The current project is a continuation of the project "Innovative Open-End Security Concept for the Development of Green Urban Neighborhoods".(2)
Replicability/Transferability
The innovation is not referred to as being transferred to new initiative(s)
Please specify Replicability/Transferability
Unknown
Impacts, benefits
Environmental impacts
Climate change
Lowered local temperature
Environmental quality
Improved air quality
Reduced noise exposure
Water management and blue areas
Increased protection against flooding
Improved stormwater management
Green space and habitat
Increased green space area
Increased conservation or restoration of ecosystems
Increased conversion of degraded land or soil
Reduced biodiversity loss
Increased number of species present
Enhanced support of pollination
Increased ecological connectivity across regeneration sites and scales
Description of environmental benefits
Climate change, environmental quality, wate management: One positive effect of green roofs is rainwater retention. From these green roof areas (based on the total annual precipitation in Hanover) approx. 250,000 m³ less rainwater flows into the urban sewage system each year compared to conventional (sealed) flat roofs. This amount of water retained on the green roofs evaporates and thus contributes to the improvement of the bio-climate in the city. In addition to these climatic effects, green roofs can also improve air quality in urban areas, since they bind and filter out air pollution (especially fine dust). (Reference 5).

Facade greening improves the microclimatic conditions on the building by reducing the temperature extremes over the course of the year. In addition to these climatic effects, greening façades can also improve air quality because they contain dusts and air pollutants tie. They also provide habitats for urban fauna and reduce noise pollution, since a green wall reflects the sound less than a smooth wall. (Reference 4, 5). Unsealed areas also help to ensure that the precipitation seeps into the ground and does not have to be drained through the sewer system. (Reference 6)

Green space and habitat : By gaining vegetation areas, biodiversity in urban areas increases. (Reference 1) Greening buildings provides a habitat for insects and especially wild bees. They are the most important pollinators of our fruit trees and berry bushes as well as many other crops. But they also ensure the reproduction of wild plants and thus the biodiversity of our landscapes. With the expansion of the program to include the aspect of unsealing, new green spaces have also been created. (Reference 2,6,7)
Economic impacts
Increased property prices
Description of economic benefits
Greening increases the property value of the houses (Reference 8)
Social and cultural impacts
Social justice and cohesion
Improved social cohesion
Improved liveability
Improved access to urban green space
Increased opportunities for social interaction
Increased involvement of locals in the management of green spaces
Health and wellbeing
Improved physical health
Improved mental health
Increased appreciation for natural spaces
Education
Increased support for education and scientific research
Increased awareness of NBS and their benefits
Description of social and cultural benefits
-Social justice and cohesion: The project offers a holistic approach and further incentives for house and land owners to upgrade the private living environment and make an additional contribution to climate protection (Reference 2).
-Health and well being: greening of buildings as well as the unsealing and planting of unnecessarily concreted areas such as courtyards, driveways etc. make a significant contribution to the well-being of the residents (Reference 2).
-Education: BUND offers tours and lectures on greening buildings and unsealing. Thy show how greening measures can enhance the living and working environment and contribute to climate protection (Reference 8).

Type of reported impacts
Achieved impacts
Indicators
-Of the approximately 32 million square meters of roof areas in the city of Hanover, 836,200 square meters (on 3131 roofs, as of 2016) have so far been planted.
-250,000 cubic meters of rainwater are not being released into the sewage system each year, but are evaporating - and this has a positive effect not only on urban temperatures but also on the water balance.( Reference 1)

Environmental, social and economic impacts
Climate action for adaptation, resilience and mitigation (SDG 13)
Climate change adaptation
Water management (SDG 6)
Flood protection
Stormwater and rainfall management and storage
Green space, habitats and biodiversity (SDG 15)
Habitat and biodiversity restoration
Habitat and biodiversity conservation
Green space creation and/or management
Environmental quality
Air quality improvement
Noise reduction
Regeneration, land-use and urban development
Regulation of built environment
Promote natural styles of landscape design for urban development
Inclusive and effective governance (SDG 16)
Inclusive governance
Effective management
Social justice, cohesion and equity (SDG 10)
Social cohesion
Health and well-being (SDG 3)
Improving mental health
Improving physical health
Analysis of specific impact categories
Job creation: The NBS created ...
No information available
Environmental justice: The implementation of the NBS project resulted in ...
Positive distribution of NBS benefits
Improved access to green and/or blue spaces
Please specify other method used to evaluate the impacts of NBS
Unknown
Negative impacts: Did the project cause any problems or concerns?
Yes
Please specify the negative impacts
While the green roofs had positive feedback, concerns about building structure and maintenance effort for green facades were voiced out by residents (Reference 9).
COVID-19 pandemic
Some events like guided tours and lectures have been cancelled before of Covid-19 (Reference 8). (no specific date mentioned on BUND website )
Methods of impact monitoring
Process of recording NBS impacts
No evidence in public records
Methods used to evaluate the impacts of NBS
Other
Evidence for use of assessment
Presence of an assessment, evaluation and/or monitoring process
Yes
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
Impact assessment mechanism
Name of any specific impact assessment tools
Unknown
Use of GIS in mapping impacts
No evidence in public records
Citizen involvement
Citizens involvement in assessment/evaluation
Unknown
Mode(s) of citizen involvement in evaluation/assessment
Other
Please specify other modes of citizen involvement in evaluation/assessment
Unknown
Citizens involvement in the analysis of the assessment/evaluation
Unknown
Follow-up to the evaluation / assessment
Unknown
References
Web links relevant to the intervention
Ref.1 (Hannover project's website)
Ref.2 (BUND project website)
Ref. 3(Hannover website)
Ref. 4 (BUND -benefits of greening buildings)
Ref 6. (BUND Project details)
Ref. 7. BUND - wild bees on green roofs
Ref. 8. (BUND -Guided Tours)
Ref. 10. Conference information
Documents relevant to the intervention
Attachment Size
Ref 10. City Development Plan (Mein Hannover 2030) (2.36 MB) 2.36 MB
List of references
1. Hannover.de. 2020. 'Greening Hannover' ('Begrüntes Hannover'). Available at: https://www.hannover.de/Leben-in-der-Region-Hannover/Umwelt-Nachhaltigkeit/Naturschutz/Mehr-Natur-in-der-Stadt/Projekte-f%C3%BCr-%E2%80%9EMehr-Natur-in-der-Stadt%E2%80%9C/Begr%C3%BCntes-Hannover. Accessed 13 July 2020.
2.Bund. (no date). 'Greening Hannover' ('Begrüntes Hannover'). Available at: http://region-hannover.bund.net/themen_und_projekte/begruentes_hannover/. Accessed 13 July 2020.
3. Hannover.de. (no date). '"More Nature in the City" continues' ('"Mehr Natur in der Stadt" wird fortgesetzt') https://www.translatetheweb.com/?from=de&to=en&ref=SERP&dl=en&rr=UC&a=https%3a%2f%2fwww.hannover.de%2fLeben-in-der-Region-Hannover%2fUmwelt-Nachhaltigkeit%2fNaturschutz%2fMehr-Natur-in-der-Stadt%2f%2522Mehr-Natur-in-der-Stadt%2522-wird-fortgesetzt. Accessed 13 July 2020.
4. BUND. (no date). ‘Good reasons for green roofs and facades’ (Gute Gründe für Dach- und Fassadenbegrünung). Available at: http://region-hannover.bund.net/themen_und_projekte/begruentes_hannover/vorteile_einer_gebaeudebegruenung/. (Accessed 13 July 2020).
5. Helmut Wahle and Dirk Schmidt. (2015). ‘Greening buildings as a climate adaptation strategy’ (Gebäudebegrünung als Bestandteil der Klimaanpassungsstrategie). Available at: https://www.hannover.de/Leben-in-der-Region-Hannover/Umwelt-Nachhaltigkeit/Naturschutz/Mehr-Natur-in-der-Stadt/Projekte-f%C3%BCr-%E2%80%9EMehr-Natur-in-der-Stadt%E2%80%9C/Begr%C3%BCntes-Hannover. Accessed 13 July 2020.
6. BUND. (2020). ‘BUND and the city of Hanover promote greenery on walls and roofs’ (BUND und Stadt Hannover fördern Grün auf Wand und Dach). Available at: http://region-hannover.bund.net/themen_und_projekte/begruentes_hannover/news/. (Accessed 13 July 2020).
7. BUND. (no date). ‘Wild bees on green roofs’ (Wildbienen auf Gründächern). Available at: http://region-hannover.bund.net/themen_und_projekte/begruentes_hannover/wildbienen_auf_gruendaechern/. (Accessed 13 July 2020).
8. BUND. (2020). ‘Guided tours and lectures 2020’ (Führungen und Vorträge 2020). Available at: http://region-hannover.bund.net/themen_und_projekte/begruentes_hannover/fuehrungen_und_vortraege_2020/. (Accessed 13 July 2020).
9. BUND. (2014). ‘Review: Conference "Paths to greening buildings in big cities"’ (Rückblick: Fachtagung „Wege zur Gebäudebegrünung in Großstädten“). Available at: region-hannover.bund.net/themen_und_projekte/begruentes_hannover/fachtagung_2014/. (Accessed 14 July 2020).
10. City of Hannover. (2016). ‘City development plan’ (Mein Hannover 2030). Available at: hannover.de. Accessed 13 July 2020.
Attachments
Attachment Size
1) Make your home sustainable (1.1 MB) 1.1 MB
2) Greening buildings as part of the strategy in Hannover (158.46 KB) 158.46 KB
3) Green roof and PV combination (368.93 KB) 368.93 KB
Additional comments
1) Make your home sustainable. Information sheet on the benefits of a sustainable houses. This includes benefits from the greening of the buildings and unsealing of areas.
2) This provides information on the strategy climate adaptation strategy of Hannover through greening buildings
3) This elaborates the integration of green roofs with photovoltaics
Comments and notes
Comments
No data was found regarding the total area of NBS. The intervention applies to the whole city of Hannover and the NBS area depends on how many applies for the subsidy for green roods and facades as well as unsealing. Reference 1 (last updated on March 12, 2020) states that since the beginning of the project, 15 000 square meters of roof areas and various facades have been greened. No records were found with regards to the status of unsealing.

No records were also found with regards to the impact evaluation of NBS as well as the monitoring activities.


Additional insights
The integration of photovoltaics with green roofs was also discussed in the project. It was mentioned that green roofs do not rule out the installation of photovoltaics. Rather, they increase the efficiency of the system by cooling the roof which prevents output reduction due to heating. The administration therefore strives to maintain its own portfolio and advises third parties accordingly to implement green roofs and photovoltaic systems in parallel on flat roofs. Restrictions exist due to the required acceptance of the increased costs and due to static conditions if these do not allow double use in terms of weight. (reference 5)

In a conference organized by BUND and the state capital of Hannover on May 21, 2014, it was mentioned that the response to green roofs had been good. By then, 1200 square meters of roofs had been greened and there were applications to green further 2800 sqm of roof area. Facade greening, on the other hand was not considered highly successful as many residents complained about the building structure and the maintenance effort. (Reference 9)
Pictures of the NBS
/sites/default/files/nbs/images/Inner%20courtyard%20in%20Linden-Sud%20after%20unsealing.jpg
/sites/default/files/nbs/images/Inner%20courtyard%20in%20Linden-Sud%20before%20unsealing.jpg
/sites/default/files/nbs/images/A%20window%20with%20wild%20wine.jpg