Prioritising the places and people that need it the most
Wir InHAUSer
Zero Carbon Refurbishment of Social Housing
This project blends affordable housing with climate action, creating new homes through sustainable modernization. By using renewable energy, innovative wastewater heat recovery, and eco-friendly materials, it reduces emissions and costs. The initiative offers affordable rents through Austria’s nonprofit housing model, with a focus on social inclusion and community involvement. A model for combining ecological sustainability & affordable living, it sets a new standard for future urban development
Austria
Local
Salzburg
It addresses urban-rural linkages
It refers to a physical transformation of the built environment (hard investment)
Yes
2022-01-31
Yes
Horizon2020 / Horizon Europe
No
Yes
Yes
Yes
As a representative of an organisation, in partnership with other organisations
The project represents an innovative response to the dual challenge of creating affordable housing while addressing climate protection. By modernizing existing buildings instead of demolishing them, the project demonstrates how to adapt housing to contemporary needs while minimizing environmental impact. The result is 24 additional affordable apartments created through sustainable construction, such as wood-based extensions with cellulose insulation.
The initiative focuses on multiple target groups, including low-income households, young families, and urban residents reliant on accessible housing. Its affordability is rooted in Austria’s nonprofit housing model and public housing subsidies, enabling rents at half the market rate.
Key climate-oriented measures include implementing a 100% renewable energy system, pioneering wastewater heat recovery, and utilizing modular, low-carbon facades. These innovations create a circular energy loop within the housing complex, reducing emissions and operational energy costs. Additionally, an alternative mobility concept encourages public transportation and cycling, further contributing to sustainable urban living.
Beyond technical solutions, the project emphasizes social inclusion. Extensive resident participation ensured acceptance of innovations while fostering community cohesion. However, the project's long-term success depends on residents’ willingness to adapt their behavior to support sustainable practices.
The project exemplifies the synergies between climate action and affordable housing. It balances ecological sustainability with social equity, demonstrating how thoughtful planning and public support can create inclusive, environmentally friendly urban spaces. By integrating resource efficiency, energy conservation, and participatory design, it establishes a replicable model for addressing global challenges like housing shortages and climate change.
The initiative focuses on multiple target groups, including low-income households, young families, and urban residents reliant on accessible housing. Its affordability is rooted in Austria’s nonprofit housing model and public housing subsidies, enabling rents at half the market rate.
Key climate-oriented measures include implementing a 100% renewable energy system, pioneering wastewater heat recovery, and utilizing modular, low-carbon facades. These innovations create a circular energy loop within the housing complex, reducing emissions and operational energy costs. Additionally, an alternative mobility concept encourages public transportation and cycling, further contributing to sustainable urban living.
Beyond technical solutions, the project emphasizes social inclusion. Extensive resident participation ensured acceptance of innovations while fostering community cohesion. However, the project's long-term success depends on residents’ willingness to adapt their behavior to support sustainable practices.
The project exemplifies the synergies between climate action and affordable housing. It balances ecological sustainability with social equity, demonstrating how thoughtful planning and public support can create inclusive, environmentally friendly urban spaces. By integrating resource efficiency, energy conservation, and participatory design, it establishes a replicable model for addressing global challenges like housing shortages and climate change.
affordable housing
zero carbon
renewable energy
alternative mobility
sustainable development
The project "Wir inHAUSer" pursues a comprehensive concept for CO₂-neutral development of existing buildings. By implementing an innovative renewable energy system and an ecological facade system, the energy demand of the residential complex has been significantly reduced and switched from fossil gas supply to 100% renewable sources. Alternative mobility solutions, such as car sharing, e-bikes, cargo bikes, and a charging station for electric vehicles, have been combined into a "Mobility Point," offering residents sustainable transportation alternatives.
Furthermore, residential space has been efficiently utilized: through densification, the number of housing units was increased from 75 to 99 without additional land sealing. The combination of various measures reduces residents' CO₂ emissions and supports compliance with the Paris Climate Agreement within the framework of social housing. The project is a pioneer in the field of sustainable urban development.
Furthermore, residential space has been efficiently utilized: through densification, the number of housing units was increased from 75 to 99 without additional land sealing. The combination of various measures reduces residents' CO₂ emissions and supports compliance with the Paris Climate Agreement within the framework of social housing. The project is a pioneer in the field of sustainable urban development.
The further development of the existing building structure was implemented with particular sensitivity to local building culture. Using ecological materials, especially timber construction and cellulose insulation in modern design, high architectural quality was achieved. The aesthetic integrates sustainability with functionality, ensuring a harmonious interplay between existing structures and new construction.
A careful intervention in the existing structure ensures the character of the residential area is preserved while creating new living quality. The redesign of open spaces, including a playground and community gardens, promotes interaction among residents and highlights the project's cultural and social values.
A careful intervention in the existing structure ensures the character of the residential area is preserved while creating new living quality. The redesign of open spaces, including a playground and community gardens, promotes interaction among residents and highlights the project's cultural and social values.
The project places great emphasis on social diversity and accessibility. The allocation of apartments was carried out by the City of Salzburg based on social criteria. Housing subsidies and rental assistance ensure affordability for diverse income groups.
The design of the residential complex promotes inclusion on multiple levels: barrier-free access and flexible apartment layouts accommodate people of all ages and needs. Shared spaces and thoughtfully designed interaction zones foster strong social cohesion
The design of the residential complex promotes inclusion on multiple levels: barrier-free access and flexible apartment layouts accommodate people of all ages and needs. Shared spaces and thoughtfully designed interaction zones foster strong social cohesion
Residents were involved in the planning process from the outset. Their needs and concerns played a central role in the design of the new housing complex. Workshops and informational events ensured transparency and acceptance. This participatory approach not only enhanced residents' identification with the project but also strengthened the social fabric of the neighborhood.
Particular attention was given to involving those directly affected by the structural changes. Their participation was a crucial factor in the successful development of the existing structures.
Particular attention was given to involving those directly affected by the structural changes. Their participation was a crucial factor in the successful development of the existing structures.
The project was characterized by close collaboration between stakeholders at local, regional, national, and European levels:
Local: The City of Salzburg, as the landowner, and the non-profit developer Heimat Österreich aimed to develop a Smart City flagship project. Architects, planners, and experts from the Salzburg Institute for Spatial Planning were involved.
Regional: Housing subsidies from the state of Salzburg played a key role in ensuring high quality and affordable rents.
National: Federal Smart City programs supported the project's CO₂-neutral renovation. Quality assurance was guided by klimaaktiv building and settlement standards.
European: Horizon programs supported the project's monitoring phase, facilitating international knowledge exchange
Local: The City of Salzburg, as the landowner, and the non-profit developer Heimat Österreich aimed to develop a Smart City flagship project. Architects, planners, and experts from the Salzburg Institute for Spatial Planning were involved.
Regional: Housing subsidies from the state of Salzburg played a key role in ensuring high quality and affordable rents.
National: Federal Smart City programs supported the project's CO₂-neutral renovation. Quality assurance was guided by klimaaktiv building and settlement standards.
European: Horizon programs supported the project's monitoring phase, facilitating international knowledge exchange
The project brought together experts from various fields: sociologists assessed residents' needs and developed socially acceptable implementation concepts. Architects and planners, supported by scientific partners, developed innovative solutions and evaluated options. Academic research provided data and analysis to assess the effectiveness of measures. This interdisciplinary collaboration created a holistic approach, integrating technical, social, and aesthetic aspects.
The implementation of the project demonstrates that ambitious goals in affordable housing and sustainability can be successfully harmonized. Since 2022, the housing complex has not only provided space for an additional 50 residents but also offers rental prices that are approximately half of the average market rate, thanks to Austria's system of nonprofit housing and housing subsidies. This significantly alleviates financial burdens for low-income households.
An innovative energy concept is at the core of the sustainability strategy. Through an optimized building envelope and the use of 100% renewable energy, previous fossil fuel systems have been entirely replaced. The concept of recovering user-dependent energy losses from exhaust air and wastewater addresses a resource that has often been overlooked. While improved construction measures, such as thermal insulation, reduce heat losses, this project tackles the challenge of reclaiming heat from wastewater and indoor air. This method closes a critical gap in energy planning and establishes a sustainable local energy cycle that minimizes energy losses.
A key success factor was the comprehensive social support provided during the construction phase. Through targeted awareness campaigns, transparent communication, and individualized assistance, residents were actively involved in the transformation process. This not only fostered acceptance but also strengthened the sense of community. This holistic approach demonstrates that technological innovations and social measures must go hand in hand to establish sustainable and long-term solutions in affordable housing.
An innovative energy concept is at the core of the sustainability strategy. Through an optimized building envelope and the use of 100% renewable energy, previous fossil fuel systems have been entirely replaced. The concept of recovering user-dependent energy losses from exhaust air and wastewater addresses a resource that has often been overlooked. While improved construction measures, such as thermal insulation, reduce heat losses, this project tackles the challenge of reclaiming heat from wastewater and indoor air. This method closes a critical gap in energy planning and establishes a sustainable local energy cycle that minimizes energy losses.
A key success factor was the comprehensive social support provided during the construction phase. Through targeted awareness campaigns, transparent communication, and individualized assistance, residents were actively involved in the transformation process. This not only fostered acceptance but also strengthened the sense of community. This holistic approach demonstrates that technological innovations and social measures must go hand in hand to establish sustainable and long-term solutions in affordable housing.
Instead of demolishing the buildings, a modernization concept was developed to adapt the existing structures to current needs and create an additional 24 apartments through vertical extensions. The central challenges were finding temporary accommodations for the 150 residents during the construction phase and designing a renovation plan that both meets climate protection requirements and ensures affordable housing in the future.
All measures related to embodied energy (building materials, structures, etc.), operational energy (electricity, heating, hot water), and everyday mobility were carefully evaluated for their costs and ecological benefits. Based on this thorough assessment of many individual puzzle pieces, a comprehensive solution emerged that harmonizes contemporary living standards, affordable rent, and climate protection.
Innovative core elements of the project include the long-term cooperative development and planning process, the implementation of vertical densification using timber construction with ecological cellulose insulation, and the installation of a novel wastewater heat recovery system, implemented at this scale for the first time in Europe. All heat is recycled and reused—essentially "from the toilet to the heating system." Additionally, an alternative mobility concept was introduced as a key component of the urban mobility transition.
All measures related to embodied energy (building materials, structures, etc.), operational energy (electricity, heating, hot water), and everyday mobility were carefully evaluated for their costs and ecological benefits. Based on this thorough assessment of many individual puzzle pieces, a comprehensive solution emerged that harmonizes contemporary living standards, affordable rent, and climate protection.
Innovative core elements of the project include the long-term cooperative development and planning process, the implementation of vertical densification using timber construction with ecological cellulose insulation, and the installation of a novel wastewater heat recovery system, implemented at this scale for the first time in Europe. All heat is recycled and reused—essentially "from the toilet to the heating system." Additionally, an alternative mobility concept was introduced as a key component of the urban mobility transition.
The technical solutions, such as the renewable energy system and modular facades, can be easily transferred to other projects. Similarly, the participatory approach -actively involving residents - is a successful model that can be applied in various contexts. The mobility strategies offer an innovative approach that is particularly valuable in urban areas facing similar challenges.
The project addresses global challenges highlighted by the New European Bauhaus:
Climate Change and Ecological Sustainability
Reduction of CO2 Emissions: Promoting climate-neutral construction methods and sustainable materials.
Resource Conservation: Strengthening circular economy practices and recycling initiatives.
Biodiversity: Encouraging green infrastructure and nature-based habitats in urban and rural areas.
Social Justice and Inclusion
Affordable Housing: Creating accessible housing for all societal groups.
Equality and Inclusion: Engaging marginalized groups and fostering an inclusive, barrier-free society.
Community and Social Cohesion: Designing living spaces that promote social interaction and inclusion.
Economic Transformation
Fostering Innovation: Supporting new technologies and approaches in construction and architecture.
Sustainable Jobs: Creating employment opportunities rooted in sustainable practices and green growth.
Strengthening Local Economic Cycles: Supporting regional production and construction processes.
Cultural Change and Education
Aesthetics and Design: Creating beautiful, functional, and sustainable environments that enhance quality of life.
Awareness Building: Promoting a new understanding of sustainable living and building practices.
Reviving Cultural Values: Merging tradition and innovation in design and architecture.
Urbanization and Sustainable Cities
Sustainable Urban Planning: Advancing compact yet livable urban spaces.
Transport and Mobility: Developing sustainable mobility concepts for cities and communities.
Resilience: Building infrastructure resilient to environmental risks and climate impacts.
Climate Change and Ecological Sustainability
Reduction of CO2 Emissions: Promoting climate-neutral construction methods and sustainable materials.
Resource Conservation: Strengthening circular economy practices and recycling initiatives.
Biodiversity: Encouraging green infrastructure and nature-based habitats in urban and rural areas.
Social Justice and Inclusion
Affordable Housing: Creating accessible housing for all societal groups.
Equality and Inclusion: Engaging marginalized groups and fostering an inclusive, barrier-free society.
Community and Social Cohesion: Designing living spaces that promote social interaction and inclusion.
Economic Transformation
Fostering Innovation: Supporting new technologies and approaches in construction and architecture.
Sustainable Jobs: Creating employment opportunities rooted in sustainable practices and green growth.
Strengthening Local Economic Cycles: Supporting regional production and construction processes.
Cultural Change and Education
Aesthetics and Design: Creating beautiful, functional, and sustainable environments that enhance quality of life.
Awareness Building: Promoting a new understanding of sustainable living and building practices.
Reviving Cultural Values: Merging tradition and innovation in design and architecture.
Urbanization and Sustainable Cities
Sustainable Urban Planning: Advancing compact yet livable urban spaces.
Transport and Mobility: Developing sustainable mobility concepts for cities and communities.
Resilience: Building infrastructure resilient to environmental risks and climate impacts.
Thousands of hours of work have gone into the project, from its inception to its completion. Many brilliant minds have contributed their expertise, and countless diligent hands have brought the ideas to life. As evidenced by the numerous awards the project has received, a flagship project has been launched. Now, it must prove what it can achieve in real life and whether it will stand the test of practical application.
Are further measures needed to fully realize the calculated energy-saving potential under real-life, everyday conditions? Is the acceptance and necessary frequency of the mobility alternatives sufficient to sustain their operation long-term? How can car-oriented user groups be encouraged to embrace cycling and public transportation? Ultimately, the sustainable success of these innovations will depend on whether residents are willing to adopt the concepts and the behavioral adjustments associated with them.
The benefits and burdens of these measures must be distributed fairly. The implementation of climate-relevant construction methods, energy systems, and new forms of everyday mobility cannot be left solely to housing cooperatives, nor can the costs be passed on to the residents. The role and responsibility of public authorities and the allocation of available funds need to be redefined. Who will cover the additional costs of innovations in regular operations once the resources and funding from ambitious, well-funded research projects are exhausted? It cannot be the residents of social housing.
Are further measures needed to fully realize the calculated energy-saving potential under real-life, everyday conditions? Is the acceptance and necessary frequency of the mobility alternatives sufficient to sustain their operation long-term? How can car-oriented user groups be encouraged to embrace cycling and public transportation? Ultimately, the sustainable success of these innovations will depend on whether residents are willing to adopt the concepts and the behavioral adjustments associated with them.
The benefits and burdens of these measures must be distributed fairly. The implementation of climate-relevant construction methods, energy systems, and new forms of everyday mobility cannot be left solely to housing cooperatives, nor can the costs be passed on to the residents. The role and responsibility of public authorities and the allocation of available funds need to be redefined. Who will cover the additional costs of innovations in regular operations once the resources and funding from ambitious, well-funded research projects are exhausted? It cannot be the residents of social housing.
