Vacant Buildings in Athens: From Mapping to Reactivation

INZEB hosts the first local workshop of the Transforming Invisible Buildings project.

Wednesday, 30 September 2026 | 10:00–12:30 | Athens

 

How can vacant buildings become part of the response to housing needs, energy challenges and the future development of our cities? What knowledge, cooperation and practical conditions are needed to bring them back into use?

 

On 30 September 2026, INZEB will host the first local workshop of the Transforming Invisible Buildings project in Athens, opening a focused dialogue on the reactivation of vacant and underutilised buildings. Under the title “Vacant Buildings in Athens: From Mapping to Reactivation”, the meeting will examine the relationship between existing buildings, energy renovation and housing needs, with particular attention to the conditions that can enable practical action in the Athens pilot.

 

The workshop is intended for representatives of local authorities, researchers, urban planners, architects, engineers, property owners and their organisations, housing practitioners, and civil society organisations working on poverty, homelessness and housing insecurity. It will provide a setting to bring together different forms of knowledge: research and data, technical and legal expertise, implementation experience, and an understanding of the needs of owners and residents. After an introductory presentation on the project and the Athens pilot, the programme will focus on an open, facilitated discussion involving all participants.

 

Transforming Invisible Buildings examines how the reactivation of vacant and underutilised buildings can support energy efficiency and reduce the need for new construction. Working across Athens, Ljubljana and Zagreb, the project connects building reuse with municipal planning and the development of approaches adapted to local circumstances. For the Athens workshop, the central question will be what is required to move from identifying an unused building to understanding whether, how and under what conditions it could return to use. The discussion will consider building condition, ownership, renovation requirements, administrative processes, financial feasibility and potential future uses. The human dimension will be equally important. Participants will be invited to explore the expectations and concerns of property owners alongside the needs of people seeking suitable and affordable housing. Attention will also be given to energy performance, thermal comfort and the ongoing costs of occupying a renovated building. By examining these dimensions together, the workshop aims to clarify the questions the Athens pilot should investigate and the expertise it will need.

 

A workshop centred on dialogue and practical experience – The meeting will begin with a presentation by INZEB introducing the project’s objectives, its approach to vacant buildings and the activities envisaged for the Athens pilot. This will establish a common starting point for the discussion and explain how participants’ contributions can inform the work ahead. The programme will then open to an exchange of observations, examples and questions. Participants will be encouraged to draw on their professional practice, research, organisational experience and work with communities. Contributions may concern a relevant dataset, an example of building reuse, a difficulty encountered during a renovation, an ownership or administrative question, or a housing need that requires closer attention.

 

What the discussion will explore:

• Understanding vacancy and the available evidence: The first part of the discussion will consider what information is available about vacant and underutilised buildings in Athens, where it can be found, and what its limitations may be. Participants will be invited to distinguish between different forms of vacancy, individual unused dwellings and entire buildings, and to identify information that could help assess reactivation potential. Research findings, local observations and experience from previous projects will all be relevant to this exchange.
• Examining the conditions for reactivation: The workshop will explore the technical, ownership-related, regulatory and financial questions that arise when considering the return of a building to use. Topics may include co-ownership, decision-making within apartment buildings, building condition, renovation requirements, potential changes of use and access to appropriate support. Discussion of the Greek institutional framework will focus on practical questions and issues requiring clarification, rather than a separate series of legal presentations.
• Connecting energy renovation with housing needs: Participants will consider how energy performance and suitable living conditions can be addressed alongside the practical feasibility of reuse. The discussion will examine renovation needs, future operating costs, affordability and the circumstances of households experiencing housing insecurity or energy poverty. Contributions from organisations working directly with residents and vulnerable groups will help bring these considerations into the exchange.
• Identifying opportunities for cooperation: A further focus will be the contribution that different organisations and professionals could make to the Athens pilot. Participants will be invited to identify relevant sources of information, examples worth investigating, expertise that could support further assessment, and opportunities for communication between municipal services, property owners, technical professionals and civil society.
• Building a basis for the Athens pilot: The workshop is intended to generate a useful working record of available knowledge, information gaps, practical obstacles and potential contributions. Its conclusions will help shape the questions pursued through the Athens pilot and identify where follow-up conversations or further investigation are needed.

This approach reflects the project’s connection between vacancy mapping, local policy labs and the development of locally adapted instruments. The wider project combines these activities with capacity building and exchange between participating cities. The closing session will bring together the main observations from the discussion, including areas of agreement, different assessments and questions that remain open. Participants will also have an opportunity to indicate how they could contribute to subsequent work.

 

Through this first local workshop, INZEB invites participants to help define the evidence, relationships and practical understanding needed to advance the Athens pilot.

 

Programme

 

About Transforming Invisible Buildings

Transforming Invisible Buildings runs from February 2026 to January 2028, with pilot activities in Athens, Ljubljana and Zagreb. The project is coordinated by Energy Cities, in partnership with Habitat for Humanity International, INZEB, the Society for Sustainable Development Design (DOOR), and the Institute for Innovation and Development of the University of Ljubljana (IRI UL). INZEB participates as the Greek project partner. The project combines vacancy mapping, stakeholder engagement, practical tools and learning between cities to explore the return of unused buildings to energy-efficient use. It also includes a replication programme for six additional cities, supporting the adaptation and testing of approaches beyond the three pilots.

 

This project is part of the European Climate Initiative (EUKI) of the German Federal Ministry for the Environment, Climate Action, Nature Conservation and Nuclear Safety (BMUKN).

 

 

Below you can find some photos from the event.