Green Roof in refurbished industrial building (Office building 22@)

Green roof at Office building 22@ Source: picharchitects
Area characterisation: 

This office building is in the Zona 22@ of Barcelona. The 22@ Barcelona urban project transforms the old industrial areas of Poblenou (Two hundred hectares) in a high-quality environment for working, living and learning. 

The area required the development of an urban planning which required the building to meet the requirements of private and public services with innovative criteria, for activities developed indoors and the building’s image within the city.

The project contemplates the revitalization of a pre-existing industrial building, from which the structure and some equipment are recycled. It tries to propose answers without the need to start from scratch.

Scale of the project: object (building, etc.)

Scales impacts from this NbS action should be assessed: object (building, etc.), neighbourhood

Urban density in which the NbS is implemented: medium


Green roof at Office building 22@ Barcelona. Source: Picharchitects Facade based on bioclimatic criteria. Source: Pich Architecs Interior of the Office building 22@ Source: Pich Architecs

Rehabilitation of an existing building by adding, among other rehabilitation measures, a semi-public green space on the roof with a positive influence on the health of users, positive effects on urban climate against the heat island effect and positive effect on water by it storages in the deck space. It also improves the energy efficiency of the building by the insulation provided by the layers of green cover.


The joint tries to answers the necessarily regeneration and recycle of buildings and obsolete neighborhoods without the necessity of destroying. Only the structure of the existing building is preserved.

The roof is projected like a green semi-public space, advisability space. There exists a big hall for multiple uses for conventions, parades and different meetings; a new “level 0” for the coexistence.

The NbS is combined with bioclimatic design. The facade is a new skin, double enclosure skin based on bioclimatic riteria for heat contribution and indoors ventilation. The new technological skin expresses the colours, textures and the use of transparencies, therefore the activities involved inside.

Potential impacts/benefits: 
  • improve the health of users,
  • reduce heat island effect,
  • increase water storage,
  • improve the energy efficiency of the building.
NbS benefits 
  • Developing climate change adaptation; improving risk management and resilience
  • Increase infiltration / Water storage
  • Reducing temperature at meso or micro scale
  • Developing climate change mitigation
  • More energy efficient buildings
  • Restoring ecosystems and their functions
  • Increase Biodiversity
  • Enhancing sustainable urbanisation
  • Changing image of the urban environment
  • Increase accessibility to green open spaces
  • Increase communities’ sense of ownership
  • Increase well-being
  • Provision of health benefits
Transferability of the result: 

Process enablers:
Economy drivers → Conditions for new business models and finance schemes

Process inhibitors:
Economy barriers → Budget constraints
Looking for solutions with low economic impact on lower interest elements, to balance the high costs of interventions with environmental and social value.


Business cluster: Organizational
Business model: Re-purpose the business for society/environment

Rehabilitation of industrial buildings for rental offices with innovation and sustainable criteria and financed by the owners community.

Temporal perspective

Expected time for the NbS to become fully effective after its implementation: short (immediately to few months)

Feedback: Still well adapetd

Expected life time of the intervention: around 25 years

Dates (for project delivered): 2004

Lessons learned: 

Main enablers factors:
The process benefit from the existing knowledge (from all the  stakeholders) regarding NbS in cities and it was possible to generate the missing knowledge.
Main inhibitor factors and how they were solved:
The process suffer from the concerns of some of the stakeholders regarding the unknown consequences.


Refurbishment financed by the owners community

Global (estimated) cost of the project: 1M€- 5M€

Cluster: public private

Financial Model: Private Finance Initiative (PFI)

NbS classification 
  • Object shapes
  • On building structures
  • Green roofs
  • Extensive green roofs
  • Strategies actions
  • Urban planning strategies

Zuzana Prochazkova, Responsible architect, R + D + i department, Pich Architects

Marta Regoyos, Acciona Ingeneria

Further information

Nature4Cities ( aims to develop a knowledge diffusion around Nature-Based Solution (NbS) and a decision support platform through new collaborative models.

This GREEN ROOF project is part of the Nature4Cities's pioneer case studies database, it will feed the observatory, NbS pre-selection and replication tools, gathered into the Geocluster4NBS.

This GREEN ROOF project was chosen as a pioneer case study for the following reasons: 1) Original criteria -> Business model (all financed by the private owners). 2) Implementation -> Rehabilitation of old industrial buildings into rental offices, adding innovative and sustainable measures.

Nature4Cities project has received funding from the European Union’s Horizon 2020 research and innovation program under grant agreement No 730468.

Urban challenges
Climate issues: 
Climate mitigation
Climate adaptation
Water management and quality: 
Urban water management and quality
Biodiversity and urban space: 
Urban space development and regeneration
Soil management: 
Soil management and quality
Public health and well-being: 
Quality of life
Environmental justice and social cohesion: 
Social cohesion
Urban planning and governance: 
Urban planning and form
Green economy: 
Bioeconomy activities
Key Performance Indicators: