The Chêne-Rond Third Place Project
Chêne-Rond : A Third Place for Community and Innovation
In Marcoussis, the Chêne-Rond third place will breathe new life into former castle outbuildings by transforming them into a space for sharing, working, and solidarity. It is part of a 20-year transition plan co-designed with residents to build a more sustainable village. Located in a neighborhood certified as "innovative and ecological neighborhoods" with 149 social housing units, it will be a place for connection, a space for learning and creating, and a resource hub for daily life.
France
Route du Chêne-Rond
91460 Marcoussis
France
91460 Marcoussis
France
Prototype level
Yes
Yes
Yes
No
No
91363: Marcoussis (FR)
The third place project in Marcoussis is part of a transition dynamic driven by residents and the municipality. It builds on two main initiatives : the co-creation of the Marcoussis 2038 transition scenario, which involved 650 citizens, and the development of the Chêne-Rond district with 149 social housing units. It addresses social, economic, and environmental challenges identified during these processes.
The overall objective is to rehabilitate an abandoned building in the Chêne-Rond district into a meeting space, fostering social diversity, neighborhood animation, and sustainable local economy. The target groups are residents of Marcoussis, surrounding areas, and local socio-economic stakeholders.
The specific objectives are: promoting diversity and solidarity by creating an inclusive space; revitalizing the neighborhood with a lively and accessible space; developing local services and activities to meet local needs; enhancing heritage by rehabilitating the former Castle's outbuildings into a sustainable space.
This third place project is the result of a long phase of reflection and co-creation. Its opening is scheduled for early 2026.
The third place will include a coworking space, modular rooms, a shared kitchen, and a restaurant. It will also house a space for manual and artistic workshops, a 2,000 m² garden, a social support area, and an apartment dedicated particularly to hosting artists. The programming of workshops and events will be co-created with residents and local associations, who will be invited to propose and lead activities. In June 2024, the municipality launched a call for applications to select stakeholders who will bring these different spaces and this vision to life.
Expected outcomes: a functional and accessible third place fostering encounters; sustainable heritage rehabilitation of the site; a viable socio-economic model for the third place; significant citizen participation.
The overall objective is to rehabilitate an abandoned building in the Chêne-Rond district into a meeting space, fostering social diversity, neighborhood animation, and sustainable local economy. The target groups are residents of Marcoussis, surrounding areas, and local socio-economic stakeholders.
The specific objectives are: promoting diversity and solidarity by creating an inclusive space; revitalizing the neighborhood with a lively and accessible space; developing local services and activities to meet local needs; enhancing heritage by rehabilitating the former Castle's outbuildings into a sustainable space.
This third place project is the result of a long phase of reflection and co-creation. Its opening is scheduled for early 2026.
The third place will include a coworking space, modular rooms, a shared kitchen, and a restaurant. It will also house a space for manual and artistic workshops, a 2,000 m² garden, a social support area, and an apartment dedicated particularly to hosting artists. The programming of workshops and events will be co-created with residents and local associations, who will be invited to propose and lead activities. In June 2024, the municipality launched a call for applications to select stakeholders who will bring these different spaces and this vision to life.
Expected outcomes: a functional and accessible third place fostering encounters; sustainable heritage rehabilitation of the site; a viable socio-economic model for the third place; significant citizen participation.
Third place
Rénovation
Co-creation
Innovation
Diversity
Eco-Responsible Heritage Rehabilitation : The project aims to rehabilitate the former outbuildings of the Château du Chêne-Rond, preserving architectural heritage while minimizing the environmental impact of new construction. Extensions will be partially built using rammed earth, a low-carbon, eco-friendly material made of compacted raw earth, known for its natural insulating properties. A circular economy approach has also been integrated, with the recovery and reuse of materials (such as paving stones, tiles, stone blocks, and ironwork), reducing waste and limiting the use of new materials.
Green Energy Production : A total of 35 photovoltaic panels will be installed on the third place’s roofs to generate energy and reduce the site's carbon footprint.
Enhancement of Outdoor Spaces : Adjacent to the buildings, a 2,000 m² plot and various outdoor areas will be used to develop an open-air project centered on nature, featuring gardening activities and environmental awareness programs.
Support for a Responsible Local Economy : For the restaurant, the project prioritizes short supply chains, sourcing local and seasonal products. The coworking space and collaborative workshops will provide a hub for local stakeholders, particularly those involved in the social and solidarity economy.
Activity Programs for Ecological Transition : Various activities will promote ecological transition and the circular economy, including : Repair and DIY workshops to encourage fixing rather than discarding ; Upcycling and renovation workshops to transform waste into useful and aesthetic objects ; Do-it-yourself (DIY) workshops promoting a zero-waste lifestyle.
This project stands out for its holistic sustainability approach, combining eco-friendly heritage rehabilitation, renewable energy production, and circular economy principles. The enhancement of outdoor spaces and engagement in local biodiversity awareness further strengthen its positive environmental impact.
Green Energy Production : A total of 35 photovoltaic panels will be installed on the third place’s roofs to generate energy and reduce the site's carbon footprint.
Enhancement of Outdoor Spaces : Adjacent to the buildings, a 2,000 m² plot and various outdoor areas will be used to develop an open-air project centered on nature, featuring gardening activities and environmental awareness programs.
Support for a Responsible Local Economy : For the restaurant, the project prioritizes short supply chains, sourcing local and seasonal products. The coworking space and collaborative workshops will provide a hub for local stakeholders, particularly those involved in the social and solidarity economy.
Activity Programs for Ecological Transition : Various activities will promote ecological transition and the circular economy, including : Repair and DIY workshops to encourage fixing rather than discarding ; Upcycling and renovation workshops to transform waste into useful and aesthetic objects ; Do-it-yourself (DIY) workshops promoting a zero-waste lifestyle.
This project stands out for its holistic sustainability approach, combining eco-friendly heritage rehabilitation, renewable energy production, and circular economy principles. The enhancement of outdoor spaces and engagement in local biodiversity awareness further strengthen its positive environmental impact.
Architectural Competition: A competition was organized to design a functional and aesthetic space that highlights the heritage of Château du Chêne-Rond. The goal is to rehabilitate this place so that it is both beautiful and adapted to the needs of the project. The rammed earth extension will provide a natural texture and earthy tones, creating an authentic atmosphere. The works began in November 2024.
Integration into the Woodland Landscape: This third place is part of a larger project to transform a former French state property into a district labeled "Innovative and Ecological" by the Île-de-France Region. The objective is to preserve a natural environment consisting of wetlands, woodlands, and meadows. Nearly 4 hectares of the wooded park have been rehabilitated, with one part open to the public and the other preserved as a senescence space.
Collaborative Spaces: The spaces will be flexible and multifunctional, suitable for various uses. The aim is also to promote the well-being of users through ergonomic furniture, careful decoration, clean and green spaces, and harmonious colors. The professional kitchen of the restaurant will be designed to meet the needs of employees with disabilities.
An Open Socio-Cultural Venue: The third place will become a driving force for local life by hosting events, activities, and socio-cultural projects. It will encourage audience diversity and civic engagement. The apartment designed for artists will promote exchanges between creators, users, and visitors.
This project combines aesthetics, functionality, and respect for the environment. The landscape integration, the use of sustainable materials such as rammed earth, and the flexible collaborative spaces will enhance the well-being and engagement of users. The artist residence and the variety of activities will make this third place an innovative, inclusive, and culturally rich space.
Integration into the Woodland Landscape: This third place is part of a larger project to transform a former French state property into a district labeled "Innovative and Ecological" by the Île-de-France Region. The objective is to preserve a natural environment consisting of wetlands, woodlands, and meadows. Nearly 4 hectares of the wooded park have been rehabilitated, with one part open to the public and the other preserved as a senescence space.
Collaborative Spaces: The spaces will be flexible and multifunctional, suitable for various uses. The aim is also to promote the well-being of users through ergonomic furniture, careful decoration, clean and green spaces, and harmonious colors. The professional kitchen of the restaurant will be designed to meet the needs of employees with disabilities.
An Open Socio-Cultural Venue: The third place will become a driving force for local life by hosting events, activities, and socio-cultural projects. It will encourage audience diversity and civic engagement. The apartment designed for artists will promote exchanges between creators, users, and visitors.
This project combines aesthetics, functionality, and respect for the environment. The landscape integration, the use of sustainable materials such as rammed earth, and the flexible collaborative spaces will enhance the well-being and engagement of users. The artist residence and the variety of activities will make this third place an innovative, inclusive, and culturally rich space.
Accessibility and Social Integration: The third place is part of a new social housing district, aiming to build connections between residents and other neighborhoods. It promotes interaction, solidarity and exchange by removing social and spatial barriers.
Inclusion of People with Disabilities: In partnership with a foundation, an Adapted Enterprise (EA) will manage the restaurant and concierge services, employing at least 55% of workers with disabilities. This model promotes access to employment, autonomy, and social integration, making the restaurant an inclusive space for exchange.
Diverse Activities to Foster Social Bonds: With a range of activities (coworking, workshops, gardening, artist residencies, etc.), the third place will encourage encourage meetings between residents, freelancers, families, people with disabilities, and associations. The shared kitchen will serve as a central hub for communal meals and events.
Accessibility: Ensuring access is a fundamental principle. Coworking prices will be adapted to different audiences (students, job seekers, etc.), and DIY and maker workshops, inspired by the fab lab model, will be accessible via affordable subscriptions.
Support for the Most Vulnerable: A social mediation space, run by the Community Social Action Center and the Red Cross, will offer administrative and digital support, as well as essential aid (food packages, tutoring). A partnership with a specialized youth prevention organization is currently being developed.
Shared Governance: The third place will implement a collaborative and transparent governance model, actively involving residents and partners.
This project exemplifies a comprehensive approach to social inclusion. It combines accessibility, diverse activities open to all, and professional integration of people with disabilities. Through shared governance and resident engagement, it offers a new way to manage a common good for the benefit of the community.
Inclusion of People with Disabilities: In partnership with a foundation, an Adapted Enterprise (EA) will manage the restaurant and concierge services, employing at least 55% of workers with disabilities. This model promotes access to employment, autonomy, and social integration, making the restaurant an inclusive space for exchange.
Diverse Activities to Foster Social Bonds: With a range of activities (coworking, workshops, gardening, artist residencies, etc.), the third place will encourage encourage meetings between residents, freelancers, families, people with disabilities, and associations. The shared kitchen will serve as a central hub for communal meals and events.
Accessibility: Ensuring access is a fundamental principle. Coworking prices will be adapted to different audiences (students, job seekers, etc.), and DIY and maker workshops, inspired by the fab lab model, will be accessible via affordable subscriptions.
Support for the Most Vulnerable: A social mediation space, run by the Community Social Action Center and the Red Cross, will offer administrative and digital support, as well as essential aid (food packages, tutoring). A partnership with a specialized youth prevention organization is currently being developed.
Shared Governance: The third place will implement a collaborative and transparent governance model, actively involving residents and partners.
This project exemplifies a comprehensive approach to social inclusion. It combines accessibility, diverse activities open to all, and professional integration of people with disabilities. Through shared governance and resident engagement, it offers a new way to manage a common good for the benefit of the community.
This third-place project is part of the Marcoussis 2038 transition plan, a roadmap for the town’s future, co-designed with citizens and socio-economic stakeholders. It sets key sustainable development priorities while placing residents’ well-being at the heart of the vision.
Between 2016 and 2017, 650 residents participated in 25 consultations (workshops, forum theater, etc.), generating 73 ideas grouped into 11 strategic priorities, which led to 100 concrete actions—including the creation of a third place. In 2018, a dedicated consultation helped define the activity hubs and functions of the future third place, aligning with the needs identified in Marcoussis 2038.
In 2024, the project entered a new phase, focusing on defining the activities, spaces, and key stakeholders who will bring the third place to life. Citizen involvement directly shaped the specifications of the call for projects launched in June 2024, leading to the selection of project leaders.
In November 2024, five organizations were chosen and are now supported by the municipality to develop their initiatives. By April 2025, they will present their projects to a steering committee, which will validate their role in the management and animation of the third place. A next key step will be the co-construction of the governance model and the socio-economic model.
At this stage, citizen participation is more emerging and the objective is to relaunch community engagement. Once the final project leaders have been selected, several actions will be launched to strengthen the involvement of residents, based on the Marcoussis 2038 framework. The priority is no longer the design of the third place but the active participation of future users in the animation of the space, the organization of activities and the conduct of collective projects. To this end, two public meetings have already been organized in 2024, as well as a public survey which collected 200 responses.
Between 2016 and 2017, 650 residents participated in 25 consultations (workshops, forum theater, etc.), generating 73 ideas grouped into 11 strategic priorities, which led to 100 concrete actions—including the creation of a third place. In 2018, a dedicated consultation helped define the activity hubs and functions of the future third place, aligning with the needs identified in Marcoussis 2038.
In 2024, the project entered a new phase, focusing on defining the activities, spaces, and key stakeholders who will bring the third place to life. Citizen involvement directly shaped the specifications of the call for projects launched in June 2024, leading to the selection of project leaders.
In November 2024, five organizations were chosen and are now supported by the municipality to develop their initiatives. By April 2025, they will present their projects to a steering committee, which will validate their role in the management and animation of the third place. A next key step will be the co-construction of the governance model and the socio-economic model.
At this stage, citizen participation is more emerging and the objective is to relaunch community engagement. Once the final project leaders have been selected, several actions will be launched to strengthen the involvement of residents, based on the Marcoussis 2038 framework. The priority is no longer the design of the third place but the active participation of future users in the animation of the space, the organization of activities and the conduct of collective projects. To this end, two public meetings have already been organized in 2024, as well as a public survey which collected 200 responses.
The design and implementation of the Chêne-Rond third place have involved multiple stakeholders at various levels.
At the local level, the municipality ensures citizen participation and integrates residents’ needs at every stage. It coordinates the project’s development and implements participatory processes to gather input from both residents and local actors. Between 2018 and 2020, the town enlisted the expertise of « Labo du 100e Singe » to conduct consultations specifically on the third place and draft a feasibility and opportunity study. In 2020, a market study assessed the viability of an inclusive restaurant employing people with disabilities.
The municipality also initiated an architectural planning phase with « Viapolis » (2020-2022) to define technical requirements and organize an architectural competition, which attracted 17 proposals. The agency « Des Clics et des Calques » was selected to oversee the project, work began in November 2024. The Paris-Saclay urban community, of which Marcoussis is a part, contributed its expertise in coworking space design, having managed similar projects in the past.
In 2023, the town engaged the consultancy « Terre d’Avance » to support the structuring of the animation collective and define the third place’s socio-economic model.
In November 2024, five project leaders were preselected to manage and animate the third place and are currently receiving support to refine their proposals.
The municipality also helped create a network of third places within the Paris-Saclay agglomeration to exchange ideas and share experiences. It also engaged with the regional third-place collective to inform its reflection.
The project is also supported by programs such as the State Brownfield Fund, the “100 Innovative and Ecological Neighborhoods” initiative of the Île-de-France Region or the Ecological Aid Fund of the Paris-Saclay Urban Community.
At the local level, the municipality ensures citizen participation and integrates residents’ needs at every stage. It coordinates the project’s development and implements participatory processes to gather input from both residents and local actors. Between 2018 and 2020, the town enlisted the expertise of « Labo du 100e Singe » to conduct consultations specifically on the third place and draft a feasibility and opportunity study. In 2020, a market study assessed the viability of an inclusive restaurant employing people with disabilities.
The municipality also initiated an architectural planning phase with « Viapolis » (2020-2022) to define technical requirements and organize an architectural competition, which attracted 17 proposals. The agency « Des Clics et des Calques » was selected to oversee the project, work began in November 2024. The Paris-Saclay urban community, of which Marcoussis is a part, contributed its expertise in coworking space design, having managed similar projects in the past.
In 2023, the town engaged the consultancy « Terre d’Avance » to support the structuring of the animation collective and define the third place’s socio-economic model.
In November 2024, five project leaders were preselected to manage and animate the third place and are currently receiving support to refine their proposals.
The municipality also helped create a network of third places within the Paris-Saclay agglomeration to exchange ideas and share experiences. It also engaged with the regional third-place collective to inform its reflection.
The project is also supported by programs such as the State Brownfield Fund, the “100 Innovative and Ecological Neighborhoods” initiative of the Île-de-France Region or the Ecological Aid Fund of the Paris-Saclay Urban Community.
In the design and implementation of the Chêne-Rond third-place project, several disciplines have been mobilized.
The municipality, as the project leader, plays a central role by bringing its knowledge of the territory and facilitating cooperation among the various local stakeholders. It coordinates the participatory approach using tools such as Visions +21 (a commission from the General Commissariat for Sustainable Development to the public innovation laboratory "Strategic Design Scenario"), to bring out, through collective intelligence, the expectations of the residents.
"The Labo du Centième Singe", an expert in social innovation and territorial ecosystems, provided its specific expertise in the development and structuring of third-places.
Architecture and urban planning are at the heart of the rehabilitation project for the Chêne-Rond commons site. They have helped define technical needs, propose layout scenarios, and prepare for the integration of future uses, while respecting the site’s particularities.
The Paris-Saclay urban community also played a role by contributing its expertise in the development of coworking spaces, having already created two similar spaces (le 21 and le 30).
The firm "Terre d'Avance", specializing in strategic and legal support, is involved in defining the economic model and governance structure.
In February 2024, a project manager was recruited to support the structuring of the collective and facilitate interactions among stakeholders, while also revitalizing the participatory dynamic with the residents.
This integrated approach, combining various skills and stakeholders, is essential for a project of such scale.
The municipality, as the project leader, plays a central role by bringing its knowledge of the territory and facilitating cooperation among the various local stakeholders. It coordinates the participatory approach using tools such as Visions +21 (a commission from the General Commissariat for Sustainable Development to the public innovation laboratory "Strategic Design Scenario"), to bring out, through collective intelligence, the expectations of the residents.
"The Labo du Centième Singe", an expert in social innovation and territorial ecosystems, provided its specific expertise in the development and structuring of third-places.
Architecture and urban planning are at the heart of the rehabilitation project for the Chêne-Rond commons site. They have helped define technical needs, propose layout scenarios, and prepare for the integration of future uses, while respecting the site’s particularities.
The Paris-Saclay urban community also played a role by contributing its expertise in the development of coworking spaces, having already created two similar spaces (le 21 and le 30).
The firm "Terre d'Avance", specializing in strategic and legal support, is involved in defining the economic model and governance structure.
In February 2024, a project manager was recruited to support the structuring of the collective and facilitate interactions among stakeholders, while also revitalizing the participatory dynamic with the residents.
This integrated approach, combining various skills and stakeholders, is essential for a project of such scale.
The Marcoussis third-place combines citizen participation, social innovation, and sustainable rehabilitation. As part of the "Marcoussis 2038" scenario, the project is embedded in a long-term vision aligned with sustainable development goals and is based on co-creation with residents and local stakeholders through an experimental approach.
Third-places, an innovative model : Situated at the crossroads of home and office, personal and collective life, these spaces disrupt traditional structures. In a context of declining local services, they are emerging as hubs of local innovation, experimenting with new ways of working, learning, and socializing.
An evolving governance model : The municipality launched a call for projects to establish a local collective responsible for managing and running the space, demonstrating a commitment to co-creation with civil society. This third-place is designed as a laboratory where governance will develop progressively.
A testing ground : Its economic model will combine grants, revenue from activities, and user contributions, with a strong focus on accessibility. Its range of services and activities will evolve based on needs and local dynamics in a logic of experimentation.
Innovation in construction : The project follows a rehabilitation and circular economy approach, using biosourced materials, reuse, and refurbished furniture. The choice of rammed earth construction, an eco-friendly technique, directly addresses contemporary environmental challenges.
This third-place represents a new way of shaping territorial development by fostering experimentation, adaptability, and collective involvement. By embracing uncertainty as a driver of innovation, it could inspire other local cities seeking to create spaces truly rooted in the needs of their communities.
Third-places, an innovative model : Situated at the crossroads of home and office, personal and collective life, these spaces disrupt traditional structures. In a context of declining local services, they are emerging as hubs of local innovation, experimenting with new ways of working, learning, and socializing.
An evolving governance model : The municipality launched a call for projects to establish a local collective responsible for managing and running the space, demonstrating a commitment to co-creation with civil society. This third-place is designed as a laboratory where governance will develop progressively.
A testing ground : Its economic model will combine grants, revenue from activities, and user contributions, with a strong focus on accessibility. Its range of services and activities will evolve based on needs and local dynamics in a logic of experimentation.
Innovation in construction : The project follows a rehabilitation and circular economy approach, using biosourced materials, reuse, and refurbished furniture. The choice of rammed earth construction, an eco-friendly technique, directly addresses contemporary environmental challenges.
This third-place represents a new way of shaping territorial development by fostering experimentation, adaptability, and collective involvement. By embracing uncertainty as a driver of innovation, it could inspire other local cities seeking to create spaces truly rooted in the needs of their communities.
Building Together: The project is based on a collaborative and participatory approach, placing citizens and local stakeholders at the core of the co-creation process. The objective is to create a third place with those who will bring it to life. This approach aims to engage each stakeholder in a long-term commitment to defining, implementing, and managing the space. Residents are not only invited to imagine the project but also to actively participate in its management and development.
A Facilitator Role : The municipality adopts a facilitator role to structure the collective and the range of activities offered within the third place. It ensures cooperation among stakeholders, fosters complementarity between initiatives to meet the needs identified during the initial consultations, and supports the establishment of a sustainable collective that will uphold the project in the long run.
Relying on External Expertise: Given the complexity of the project, the municipality has sought external expertise and project management assistance for various aspects: designing a third place tailored to the territory, developing an architectural program that balances heritage preservation with new uses, and structuring the legal and economic framework to ensure the model's viability.
A Progressive and Adaptive Deployment: The approach is flexible and iterative, allowing the project to be adjusted according to evolving needs and circumstances.
Key Phases of the Project :
✔Consultation and co-construction with residents
✔ Feasibility and opportunity studies for a third place in Marcoussis
✔ Architectural programming and competition
✔ Recruitment of a project manager
✔ Launch of a call for projects to identify operators
✔ Support for selected operators and definition of the socio-economic model
✔ Start of construction work and site supervision
✔ Renewed citizen participation and formation of a residents’ collective
✔ Official launch and activity experimentation
A Facilitator Role : The municipality adopts a facilitator role to structure the collective and the range of activities offered within the third place. It ensures cooperation among stakeholders, fosters complementarity between initiatives to meet the needs identified during the initial consultations, and supports the establishment of a sustainable collective that will uphold the project in the long run.
Relying on External Expertise: Given the complexity of the project, the municipality has sought external expertise and project management assistance for various aspects: designing a third place tailored to the territory, developing an architectural program that balances heritage preservation with new uses, and structuring the legal and economic framework to ensure the model's viability.
A Progressive and Adaptive Deployment: The approach is flexible and iterative, allowing the project to be adjusted according to evolving needs and circumstances.
Key Phases of the Project :
✔Consultation and co-construction with residents
✔ Feasibility and opportunity studies for a third place in Marcoussis
✔ Architectural programming and competition
✔ Recruitment of a project manager
✔ Launch of a call for projects to identify operators
✔ Support for selected operators and definition of the socio-economic model
✔ Start of construction work and site supervision
✔ Renewed citizen participation and formation of a residents’ collective
✔ Official launch and activity experimentation
The third-place project in Marcoussis is based on a structured and documented approach, which can be easily transferred to other territories. Several elements and tools can be adapted to different contexts.
Consultation method: The participatory approach, initiated with "Marcoussis 2038", relies on facilitation tools that gather citizens’ needs, identify their aspirations, prioritize actions, and define a program and action plan. This phase has already been well documented and shared, and the municipality continues to build on it.
Identification of stakeholders and co-construction: The call for projects aimed at identifying local stakeholders, the dissemination method, the framework for responding to stakeholders, and the selection criteria can be adapted to other projects. For this phase, the municipality has also drawn inspiration from other third-place initiatives. The co-construction phase with stakeholders, which is about to begin, will involve the use of various tools and facilitation methods, such as co-development meetings and co-design workshops. This phase will also be documented to be shared.
Governance and modeling: A reflection on the governance and legal and economic structuring of the third-place is underway. The lessons learned from this phase will be valuable for other similar projects, as it is a complex aspect of the initiative.
In summary, the Marcoussis model offers a concrete approach based on collective intelligence and co-construction tools, transferable to other contexts. As a public authority, the municipality also has the responsibility to document this process to account for its effectiveness and share it with residents, partners, and other territories wishing to develop similar projects.
Consultation method: The participatory approach, initiated with "Marcoussis 2038", relies on facilitation tools that gather citizens’ needs, identify their aspirations, prioritize actions, and define a program and action plan. This phase has already been well documented and shared, and the municipality continues to build on it.
Identification of stakeholders and co-construction: The call for projects aimed at identifying local stakeholders, the dissemination method, the framework for responding to stakeholders, and the selection criteria can be adapted to other projects. For this phase, the municipality has also drawn inspiration from other third-place initiatives. The co-construction phase with stakeholders, which is about to begin, will involve the use of various tools and facilitation methods, such as co-development meetings and co-design workshops. This phase will also be documented to be shared.
Governance and modeling: A reflection on the governance and legal and economic structuring of the third-place is underway. The lessons learned from this phase will be valuable for other similar projects, as it is a complex aspect of the initiative.
In summary, the Marcoussis model offers a concrete approach based on collective intelligence and co-construction tools, transferable to other contexts. As a public authority, the municipality also has the responsibility to document this process to account for its effectiveness and share it with residents, partners, and other territories wishing to develop similar projects.
The Chêne-Rond third place is part of the "Marcoussis 2038" plan, which led to the creation of the ROAD (Sustainable Action Objectives Report), a strategic document approved by the municipal council. This report outlines 11 key priorities, broken down into concrete actions throughout the mandate. One of the key features of the ROAD is the integration of the United Nations Sustainable Development Goals (SDGs), ensuring a link between local initiatives and global sustainability challenges.
The third place aligns with Priority 11: "Developing a local and responsible economy" and connects to several SDGs.
SDG 1 - No Poverty : Social and professional integration through local jobs and activities and services accessible to the most vulnerable (target 1.4).
SDG 2 - Zero Hunger : Promotion of organic farming, healthy eating, and combating food waste.
SDG 3 - Good Health and Well-being : Reduction of stress related to commuting, strengthening social ties, and promoting balanced diets (target 3.4).
SDG 4 - Quality Education : A space for lifelong learning.
SDG 8 - Decent Work and Economic Growth : Inclusive coworking, support for social and solidarity economy (SSE) and local innovation (target 8.5).
SDG 9 - Industry, Innovation, and Infrastructure : Rehabilitation of abandoned buildings into a activity centers and access to technologies (targets 9.1 and 9.c).
SDG 10 - Reduced Inequalities : Local jobs and proximity services to address socio-economic disparities.
SDG 11 - Sustainable Cities and Communities : Participatory urbanization and reduction of environmental impact (targets 11.3 and 11.6).
SDG 12 - Responsible Consumption and Production : Recycling and waste reduction through the Fablab, workshops, and repair activities like Repair Café (target 12.5).
SDG 16 - Peace, Justice, and Strong Institutions : Participatory and inclusive governance (target 16.7).
The third place aligns with Priority 11: "Developing a local and responsible economy" and connects to several SDGs.
SDG 1 - No Poverty : Social and professional integration through local jobs and activities and services accessible to the most vulnerable (target 1.4).
SDG 2 - Zero Hunger : Promotion of organic farming, healthy eating, and combating food waste.
SDG 3 - Good Health and Well-being : Reduction of stress related to commuting, strengthening social ties, and promoting balanced diets (target 3.4).
SDG 4 - Quality Education : A space for lifelong learning.
SDG 8 - Decent Work and Economic Growth : Inclusive coworking, support for social and solidarity economy (SSE) and local innovation (target 8.5).
SDG 9 - Industry, Innovation, and Infrastructure : Rehabilitation of abandoned buildings into a activity centers and access to technologies (targets 9.1 and 9.c).
SDG 10 - Reduced Inequalities : Local jobs and proximity services to address socio-economic disparities.
SDG 11 - Sustainable Cities and Communities : Participatory urbanization and reduction of environmental impact (targets 11.3 and 11.6).
SDG 12 - Responsible Consumption and Production : Recycling and waste reduction through the Fablab, workshops, and repair activities like Repair Café (target 12.5).
SDG 16 - Peace, Justice, and Strong Institutions : Participatory and inclusive governance (target 16.7).
The project for the third place is entering a decisive phase, with an opening planned for early 2026. This phase builds on several years of co-construction, embodying the values of the NEB: combining expertise, fostering and valuing citizen involvement, promoting inclusion, and designing a functional, inspiring, and resilient space.
Finalization of the governance model: In 2025, significant work will be carried out with the facilitators and managers to structure the activities, define the shared governance model, and develop the socio-economic model.
Monitoring of construction and layout: The construction work is expected to be completed by November 2025. A call for tenders will soon be issued for the layout of the spaces, in collaboration with the project leaders, focusing on design, ergonomics, and reuse of materials.
Communication and mobilization: Communication efforts will be intensified to inform and engage residents and partners. A series of podcasts on the urban development of Marcoussis and the third place is being prepared, created in partnership with a theater company and a class of 4th graders. These podcasts will be regularly broadcasted prior to the opening.
Resident involvement: A first group of residents is already involved in managing the garden, and an association has been created to oversee this space. In the second half of 2025, a group of residents will be brought together to organize activities and participate in the governance of the space. To structure this approach, the municipality is considering a partnership with an association specializing in creating citizen collectives at the neighborhood level, based on a proven methodology.
The opening in 2026 will mark the start of a year of prefiguration, during which activities, rates, and the organization of spaces will be tested and adjusted to ensure the space fully meets the needs of the territory and its residents.
Finalization of the governance model: In 2025, significant work will be carried out with the facilitators and managers to structure the activities, define the shared governance model, and develop the socio-economic model.
Monitoring of construction and layout: The construction work is expected to be completed by November 2025. A call for tenders will soon be issued for the layout of the spaces, in collaboration with the project leaders, focusing on design, ergonomics, and reuse of materials.
Communication and mobilization: Communication efforts will be intensified to inform and engage residents and partners. A series of podcasts on the urban development of Marcoussis and the third place is being prepared, created in partnership with a theater company and a class of 4th graders. These podcasts will be regularly broadcasted prior to the opening.
Resident involvement: A first group of residents is already involved in managing the garden, and an association has been created to oversee this space. In the second half of 2025, a group of residents will be brought together to organize activities and participate in the governance of the space. To structure this approach, the municipality is considering a partnership with an association specializing in creating citizen collectives at the neighborhood level, based on a proven methodology.
The opening in 2026 will mark the start of a year of prefiguration, during which activities, rates, and the organization of spaces will be tested and adjusted to ensure the space fully meets the needs of the territory and its residents.
