1. General information
Location and description of the intervention
City or FUA
Stuttgart
Region
Europe
Native title of the NBS intervention
Grüner Dachhof
Short description of the intervention
In 2008 the new building of the WGV-Insurance has been opened in Stuttgart. Since then customers and employees of the WGV have enjoyed the beautiful courtyards which contribute to a good working environment. The approx. 3.6 ft. (1.1 m) high, built-in planters have been provided with an automatic irrigation system with the irrigation pipes installed below the elevated concrete slabs. The four courtyards have been planted with a total of 58 small crowned trees. In addition, several extensive green roof areas of approx. 21,600 sq. ft. (2,000 m²) total were installed to improve the Stuttgart climate. (1, 6).
Address

Tübinger Str. 51
70178 Stuttgart
Germany

Location
Point location, which indicates where the NBS takes place
Total area
3650.00m²
NBS area
3650.00m²
Type of area before implementation of the NBS
Building
Website of the intervention
https://zinco-usa.com/references/wgv-insurance-stuttgart-germany
Timeline of intervention
Start date of the intervention (planning process)
2007
Start date of intervention (implementation process)
2008
End date of the intervention
2008
Present stage of the intervention
Completed
Goals of the intervention
1. Reduce air conditioning costs (5)
2. Create a windbreak, reducing chill (5)
3. Reduce heating demands in winter (5)
4. Creating a good working environment (6)
5. Increase aesthetic appreciation of the company's office spaces (6)
6. To improve urban air quality (5)
Quantitative targets
1. Installing of 2,000 m² of a new green roof space

The other initial quantitative targets are unknown
Monitoring indicators defined
1. Savings in fuel heating costs estimated at litres of fuel oil/m2/year (5)
2. Decrease of albedo level in °C (5)
Sustainability challenge(s) addressed
Climate action for adaptation, resilience and mitigation (SDG 13)
Climate change mitigation
Green space, habitats and biodiversity (SDG 15)
Green space creation and/or management
Environmental quality
Air quality improvement
Health and well-being (SDG 3)
Improving mental health
Creation of opportunities for recreation
Climate change mitigation: What were the goals of the NBS?
Reduce energy demand, with the use of renewables or energy efficiency improvements
Climate change mitigation: What activities are implemented to realize the conservation goals and targets?
Install vertical or horizontal artificial surfaces that help with carbon storage and cooling
Implementation activities
1. Installation of the Stabilodrain® SD 30 elements in an inner courtyard (1)
2. Installation of automatic irrigation system for plants growing (6)
3. Increasing the surface roughness of the building's roof (for a reduction in local wind velocities) (5)
Type of NBS project
Creation of new green areas
NBS domain and interventions
Ecological domain(s) where the NBS intervention(s) is/are implemented
Nature on buildings (external)
Green roofs
Grey infrastructure featuring greens
Other
Please specify "other urban green space connected to grey infrastructure"
Green courtyard
Type of Green Roof
Extensive Green Roof: depth 3 - 5 inches; plants: Mosses, Sedums, Succulents, Herbs and few Grasses; Low maintenance and costs
Semi-intensive Green Roof: depth 5 - 7 inches; plants: Selected Perennials, Sedums, ornamental Grasses, Herbs and little Shrubs; Medium maintenance and costs
Vegetation Type
Shrubs
Trees
Please specify how many trees were planted
58
Amenities offered by the NBS
Benches and drinking water stations
Services
Expected ecosystem services delivered
Regulating services
Local climate regulation (temperature reduction)
Air quality regulation
Carbon storage/sequestration
Habitat and supporting services
Maintenance of genetic diversity
Cultural services
Aesthetic appreciation
Recreation
Scale
Spatial scale
Sub-microscale: Street scale (including buildings)
Beneficiaries
Primary Beneficiaries
Private sector/Corporate/Company
Citizens or community groups
Governance
Governance arrangements
Led by non-government actors
Non-government actors
Private sector/Corporate/Business
Please specify the roles of the specific government and non-government actor groups involved in the initiative
Architecture/Design of the roof garden was completed by Kunder³ Landscape Architecture (Stuttgart) with a contribution by Uecker + Pfaff GmbH, Stuttgart and Garten Moser GmbH & Co. KG, Reutlingen. The green roof technological systems were installed by the ZinCo Company. Project Customer - WGV Insurance. (1, 3)
Key actors - initiating organization
Private sector/corporate actor/company
Land owners
Private sector or company
Key actors - Other stakeholders involved (besides initiating actors)
Private sector/corporate actor/company
Land owners
Private sector or company
Participatory methods/forms of community involvement used
Unknown
Policy drivers
NBS intervention implemented in response to an Regional Directive/Strategy
Yes
Please specify the "Regional Directive/Strategy"
1. Guidelines for the Planning, Construction and Maintenance of Green Roofing – Green Roofing Guideline (The Landscape Development and Landscaping Research Society e. V. (FLL)) (7)
2. Recommendations for the Planning and Construction of Traffic Areas on Buildings
(The Landscape Development and Landscaping Research Society e. V. (FLL)) (7)
3. Eurocode 1 (EN 1991) Actions on structures
- Part 1-1: Densities, self-weight, imposed loads for buildings (EN 1991-1-1)
- Part 2: Traffic loads on bridges (EN 1991-2) (7)
4. Eurocode 2 (EN 1992) Design of concrete structures
- Part 1-1: General rules, and rules for buildings (EN 1992-1-1) (7)
NBS intervention implemented in response to a national regulations/strategy/plan
Yes
Please specify the national regulations/strategy/plan
1. Waterproofing of buildings - German Standard DIN 18195 (7)
2. Regulations for Roofs with Waterproofing – Flat Roof Guideline (Organization of German Roofer Society ZVDH) (7)
3. A number of guidelines, technical bulletins and additional technical contract terms of the German Road and Transportation Research Association (FGSV) (7)
4. The Federal Nature Conservation Act requires mitigation for the ecological impact of building construction. This means that green roofs are often required by conditions attached to construction permits (5).
NBS intervention implemented in response to a local regulation/strategy/plan
Yes
Please specify the "local regulation/strategy/plan"
Since 1986, the local government has required any new building with a roof pitch below 12 degrees to be equipped with a green roof – a regulation that was extended in 1993 to encompass all new buildings (7).
Mandatory or voluntary intervention
Voluntary (spontaneous)
Enablers
Presence of specific city-level GI/NBS vision/strategy/plan - mentioned in connection to the project
Unknown
Presence of specific city-level GI/NBS section/part in a more general plan - mentioned in connection to the project
Yes
Please specify the general plan with GI/NBS section
193 large cities in Germany, 29 (including, Berlin, Boblingen, Frankfurt, Karlsruhe, Kassel, Leonberg and Stuttgart) give direct support to "roof greening". The policy includes a financial support ranging from €5 - €50 (£3 -£30) /m2, or between 25 – 100% of the installation cost. The League of Cities in Germany supports the idea, citing the significant saving in heating and air conditioning costs. Indirect aid for green roofs is provided in other ways, for example, 17% of German cities offer reduced sewage disposal charges for developments with green roofs (5).
If there is a relevant strategy or plan, please specify the theme / type of the plan.
City specific green space strategy or plan
Presence of city network or regional partnerships focused on NBS - mentioned in connection to the project
Yes
Please specify
Green Roof Association DDV (Deutscher Dachgärtner Verband) (2)
Presence of GI / NBS research project - mentioned in connection to the project
Yes
Please specify
1. (2003). Green Roofs: their existing status and potential for conserving biodiversity in urban areas. English Nature Research Reports (includes the analysis of examples from Stuttgart and analogous ZinCo projects).
Subsidies/investment for GI / NBS in the city - mentioned in connection to the project
Yes
Please specify
1. Approx. 50, 000 m² of green roof space have been subsidized by municipal agencies in Stuttgart alone, although a lot more has been simply mandatory. These subsidies are led by the city concept of roof greening that aims at air quality improvement, and sustainable urban development (3).
Co-finance for NBS
No
Co-financing governance arrangements
No
Was this co-governance arrangement already in place, or was it set up specifically for this NBS?
No
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)
Unknown
Source(s) of funding
Public local authority budget
Corporate investment
Type of fund(s) used
Direct funding (grants, subsidies, or self-financed projects by private entities)
Non-financial contribution
No
Business models
Green densification model
Which of the involved actors was motivated by this model?
Private for-profit actor (e.g. firm, insurer)
Type of innovation
Technological
Product innovation
Please specify technological innovation
The approx. 3.6 ft. (1.1 m) high, built in planters have been provided with an automatic irrigation system with the irrigation pipes installed below the elevated concrete slabs (6).
Novelty level of the innovation
The innovation is copied/derived from previous initiative(s) with substantial adaptation
Please specify novelty level of the innovation
The first green roof with automatic irrigation systems similar to what ZinCo used was installed at Allianz Insurance Company office building by Jörg Breuning in 1984 (2).
Replicability/Transferability
The innovation is transferred to new initiative(s) with substantial adaptation
Please specify Replicability/Transferability
Technological principles of WGV roof garden were developed and implemented in the case of the High Line Park in New York completed by ZinCo in 2009 (4).
Impacts, benefits
Environmental impacts
Climate change
Lowered local temperature
Reduced emissions
Enhanced carbon sequestration
Green space and habitat
Increased green space area
Description of environmental benefits
(1) The four courtyards have been planted with a total of 58 trees, providing space for biodiversity in the area.
(2) The planters have been provided with an automatic irrigation system, which reduces water consumption.
(3) The green spaces have contributed to the positive control of the Stuttgart climate. They have helped to reduce the scorching heat in the summer and provided shade to the building. It also helped in reducing the energy demand of the building. The crowned trees also provide a good sink for carbon storage. (1, 3, 7)
Economic impacts
Reduce financial cost for urban management
Description of economic benefits
The project reduces energy demand and the associated costs. (1)
Social and cultural impacts
Social justice and cohesion
Improved access to urban green space
Health and wellbeing
Improved mental health
Description of social and cultural benefits
The white coloured Tulips and Vinca brightens up the courtyard, This makes the place aesthetically pleasant. Employees enjoy the view of the courtyard from their offices, and the view help creating positive vibes in the working environment. The water features add a relaxing environment. (1, 3, 5)
Type of reported impacts
Achieved impacts
Indicators
1. Savings in fuel heating costs have been estimated at 2 litres of fuel oil/m2/year for a typical green roof in Germany (ZinCo 2000) (5).
2. Decrease of albedo level lead to decrease of the re-rediant heat at night (report). Flat gravel covered roofs may be up to 21°C hotter than vegetated roofs (Ibid).
Environmental, social and economic impacts
Climate action for adaptation, resilience and mitigation (SDG 13)
Economic development and employment (SDG 8)
Environmental quality
Green space, habitats and biodiversity (SDG 15)
Health and well-being (SDG 3)
Regeneration, land-use and urban development
Analysis of specific impact categories
Job creation: The NBS created ...
No information available
Environmental justice: The implementation of the NBS project resulted in ...
Improved access to green and/or blue spaces
Negative impacts: Did the project cause any problems or concerns?
No information was found regarding negative impacts of the project
COVID-19 pandemic
Unknown as of September, 2020.
Methods of impact monitoring
Process of recording NBS impacts
Conduct a baseline survey before and after NBS implementation
Methods used to evaluate the impacts of NBS
Focus groups
Questionnaire surveys / online surveys
Evidence for use of assessment
Presence of an assessment, evaluation and/or monitoring process
Unknown
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
Citizens involvement in the analysis of the assessment/evaluation
Unknown
Follow-up to the evaluation / assessment
Unknown
References
Web links relevant to the intervention
ZinCo Official Page
The First Green Roof in Stuttgart
Stuttgart Green Roof
Zinco Greenroof
Documents relevant to the intervention
Attachment Size
Evaluation Report (778.53 KB) 778.53 KB
Project Profile data (915.5 KB) 915.5 KB
ZinCo Walkways Planning Guide (4.72 MB) 4.72 MB
nbs_stuttgart_example.pdf (3.73 MB) 3.73 MB
List of references
1. (2017). ZinCo Green Roof Projects. Available at: https://zinco-greenroof.co.uk/references/wgv-insurance-stuttgart. Accessed on 14th September, 2020.
2. (2014). Green Roof of the Year 2014, Available at: http://www.greenrooftechnology.com/green-roof-blog/green-roof-of-the-year-2014. Accessed on 14th September, 2020.
3. Greenroof. (2018). WUERTTEMBERGISCHE GEMEINDEVERSICHERUNG A.G. (WGV), HEADQUARTERS. Available at: https://www.greenroofs.com/projects/wuerttembergische-gemeindeversicherung-a-g-wgv-headquarters/. Accessed on 14th September, 2020.
4. Project Profile Data WGV-Insurance, Stuttgart, Germany. Available at: https://zinco-usa.com/sites/default/files/2019-05/ZinCo_Parking_Garage_WGV.pdf. Accessed on 14th September, 2020.
5. (2003). Green Roofs: their existing status and potential for conserving biodiversity in urban areas. English Nature.
6. (2016). Planning Guide. Walkways and Pathways on Roofs and Decks. ZinCo GmbH.
7. (2017). ICLEI Briefing Sheet - Nature-based Solutions, http://unfccc.int/files/parties_observers/submissions_from_observers/application/pdf/778.pdf. Available at: Accessed on 14th September, 2020.
Comments and notes
Comments
Evaluation reports for this particular projects are not found so far.
Pictures of the NBS
/sites/default/files/nbs/images/wgv1.jpg
Public Images
Green Roof Courtyard of the WGV Insurance Building (2008)
Green Roof Courtyard of the WGV Insurance Building (2008)
ZinCo, retrieved 08/17/2018 from Joachim Stroh
Green Roof Courtyard of the WGV Insurance Building (2008)
Green Roof Courtyard of the WGV Insurance Building (2008)
ZinCo, retrieved 08/17/2018 from Joachim Stroh