Vitoria-Gasteiz retrofitting package

VG_retrofitting package1

Main sector:

  • District energy
  • Smart buildings


The building renovation intervention consists mainly of envelope retrofitting, which involves the intervention in the façade and roof, improving envelope’s insulation and air-tightness and installing new low-energy windows, if needed. The Coronación neighbourhood was chosen in Vitoria Gasteiz for this intervention as it was identified as the city’s most vulnerable neighbourhood in terms of social issues, stability, habitability, accessibility and energy efficiency. This district reflects the major challenges in terms of retrofitting and implementation of smart city concepts: very high density, low-medium income and relevant social dimension.

Following the diagnosis of the residential buildings in the demo area (1,913 dwellings), six main typologies (from the energy point of view) have been identified. The refurbishment of up to 750 homes is co-financed by the SmartEnCity project, and the Basque Country Government agreed to co-finance in the same way for any other building in the demo area, if this number was exceeded. Finally, 27 residential buildings and other tertiary buildings joined the project summing an equivalent energy consumption around the initially expected from 750 dwellings. Preliminary design projects for building retrofitting were developed for a sample building of each typology, aiming for ambitious energy savings.

According to the technical specifications required to comply with the energy refurbishment of the buildings, as well as the connection to the biomass district heating, it is essential to have teams of designers (architects and technical architects) with experience and technical competence that guarantees the success of the solutions. Due to the terms of the Public Sector Contracting Law and with the technical solvency in mind, Visesa agreed, with the support of COAVN and COATA (official colleges of architects and surveyors), a basis for the tender for a framework agreement that would allow for a stock of teams with guaranteed technical solvency. In October 2016, the tender was published and an agreement with 55 selected teams meeting the specified requirements was signed. In May 2017 and June 2018, two-day training sessions were held with 105 professionals from the agreement list, explaining the technical conditions of the rehabilitation projects, the characteristics of the connection to the district heating, as well as general explanations on energy-efficient refurbishment and good practices. As separate contracts with the neighbours are signed, the projects will be tendered within the list of 55 teams with which the agreement has been signed.

In July 2018 a major milestone was reached with the beginning of the first retrofitting works on the two communities catalogued as early adopters. By the end of 2019, 11 buildings were already retrofitted and monitoring kits were installed in more than half the total of dwellings to assess their comfort level before and after the retrofitting process. Energy consumption in each dwelling is, as well, measured with the purpose of evaluating the impact of the intervention. Now, beginning of 2021, the project has reached its final phase and It is expected that all remaining blocks and District Heating deployment will be finished in in summer 2021 and, by then, the district will finally show its final attractive and energy-efficient appearance.

Business model:

The estimated costs for the retrofitting interventions are 21,000 EUR on average per dwelling, including the connection to the district heating network. There are some buildings where the costs are higher because of its initial characteristics (more complex interventions due to existing walls). The final price for the house owners, after discounting the H2020, Basque Government and Vitoria Gasteiz Municipality grants, is 9,600 EUR on average. In addition, the Basque Government and Vitoria Gasteiz Municipality created a guarantee fund for those who cannot afford this investment.

VISESA housing public company has an innovative role as “delegate promoter” of the retrofitting actions, on behalf of the Communities of home owners.  Through agreements signed between both parties, VISESA manages, contracts, supervises and finances the correct design and execution of the rehabilitation works, delivering the final product “turnkey” to its owners and charging them the cost difference less subsidies. VISESA also manages the different subsidies administrative tasks (application, justification, etc.) as "one-stop-shop agency“, discharging the neighbours of these cumbersome task.

The current heating and domestic hot water costs per dwelling are estimated to be around 600 EUR/year on average, corresponding to about 5,000 kWh for heating and 1,300 kWh for domestic hot water. In the case of Vitoria Gasteiz, as part of the intervention, the neighbours must change from individual heating systems to the district heating system. It is expected that the costs of district heating will be substantially lower than those related to actual costs, including maintenance and substitution of individual systems. The payback period for the intervention, purely based on recovering the investment from the savings on the operation and taxes on the buildings, is about 30 years. Additional benefits to the building which are not included in this calculation are for example the increased value on the property or the health and comfort benefit for the residents.

Citizen engagement:

Community involvement and citizen engagement is particularly relevant due to the nature of the building retrofitting interventions. The interventions are carried out in private dwellings and the residents’ opinion is decisive. In Spain, if the majority of a building’s residents do not agree with the intervention, this might be an insurmountable barrier for the action.

Various agents are involved in the discussions about building refurbishment in Coronación District, including Errota Zaharra and Bizilagun neighbours’ associations, Aparejual, Nagusilan, Ekologistak Martxan and Gaden associations, Coronación church, Coronación mosque, Health Centre, Elderly People Sociocultural Centre, foreign people collectives, and SEA Catering and Gasteiz On commercial associations. This degree of involvement shows that citizens are the foundation of the project. They have been engaged in the definition process and will be involved in co-creation workshops to design the neighbourhood intervention. 

In the beginning of the project, flyers were distributed to the neighbours and a municipal website was set up in order to make the main information accessible to all inhabitants interested in the project in Vitoria Gasteiz. A communication plan was also developed, including actions such as workshops and other awareness actions, which are carried out throughout the whole project. An office was opened in 2017 in the heart of the neighbourhood to inform all the people interested, working as the communication hub between neighbours and the project consortium and, later on, as technical office to coordinate retrofitting works. An Information and Consultation Strategy was also launched in September 2016 to consult citizens about different alternatives related to district renovation and urban planning. 

In addition, once retrofitting works conclude, some citizen engagement actions are taken to ensure the proper user behaviour in the renovated dwellings and to prevent eventual issues now that the dwellings’ characteristics have changed. Some material has been developed to this respect and has been disseminated among participant building’s neighbours.

At the same time, learnt lessons and conclusions from this citizen engagement task have been gathered and summarized in a document, and a selection of tools and resources has been done creating a toolkit. This material is supposed to be useful for follower or interested cities to replicate SmartEnCity results.



  • Increased property values
  • Increased health and quality of life
  • Increased energy efficiency
  • Reduction of energy bills
  • Reduction of carbon emissions
  • Increased comfort
  • Social integration
  • Job creation
  • Behavioral change


Investment/Finance:  ca. 15 million €

Potential for replication:

With many cities in Europe having serious problems with thermal performance in a significant part of their building stock, opportunities for replicating energy efficiency related renovation solutions are plentiful. The management of these renovation processes, including involvement of public and private sectors, citizen engagement practices and regulatory and contracting practices that have been implemented within the SmartEnCity project in Vitoria-Gasteiz can serve as a good basis for replication in many other cities.

Facts & Figures

26 buildings (302 dwellings) dwellings were retrofitted and connected to the new biomass district heating network carried out within the frame of SmartEnCity with the following results:

  • 90% reduction of CO2 emissions
  • Savings of up to 50% in heating 
  •  Average savings of 20% in household energy bills. 
  •  Energy Certification A in all the rehabilitated properties. 
  • Total substitution of gas by renewable energy sources for domestic hot water and heating: local biomass. Lower CO2 print.
  •  Aesthetic Improvement of the neighbourhood and increased property values. 
  •  Improvement in comfort in the dwellings: fewer temperature changes and less overheating in summer. 
  •  Efficient use of rehabilitated dwellings by informed residents with better controlling capability thanks to the installed monitoring systems. 
  •  Extension of the new District Heating Network to other buildings and installations in the neighbourhood (church and gymnasium-spa)

Lessons Learned

  • Engage citizens from the boundaries
  • Empowered citizens, efficient dwellings

Pictures @VISESA