Urbana, or PGOU) to guide development. The PGOU frameworks introduced by this law often included provisions to increase housing density in urban centers, especially in cities experiencing rapid population growth. Cities like Madrid and Barcelona began preparing urban plans that incorporated compact city principles, helping to manage their expanding populations.

Throughout the 20th century, various **Plan Nacional de Vivienda (National Housing Plans)** were introduced to address housing shortages and improve living conditions across Spain. These plans often focused on the construction of social housing in urban areas, contributing to rising population density in cities such as Valencia, Seville, and Bilbao. These housing developments typically consisted of multi-story apartment blocks built within existing urban boundaries.

In 1992, the **Ley del Suelo** was revised to yet again curb urban sprawl. This revision prioritized urban renewal and redevelopment over the expansion of urban peripheries and introduced stricter requirements for municipalities to justify land-use changes. By promoting urban renewal and infill development, the 1992 law implicitly encouraged densification and set the stage for future policies that would explicitly prioritize compact urban development.

During the 1980s and 1990s, the first decades of democracy following the death of the dictator Francisco Franco (1975), many Spanish cities adopted their own urban development plans, often shaped by national laws and regional policies. For example, Barcelona's urban plan following the 1992 Olympics emphasized the redevelopment of industrial zones into residential and mixed-use areas, laying the groundwork for modern densification efforts – albeit leading to expulsions and urban cleansing of working-class communities while marking the end of barraquismo<fnref n="168" /> in the city. Similarly, in Madrid, urban renewal projects in districts such as Lavapiés aimed to increase population density while preserving the ‘historical fabric’ of the city.

The foundation for densification efforts in Spain was laid in 2000 with the **Urban Planning Law (Ley de Ordenación del Territorio y Urbanismo)**, which introduced several core principles of land use planning in Spain. These principles emphasized compact urban growth, prioritizing infill development over expansion into greenfield areas, and promoting mixed-use developments to integrate residential, commercial, and public spaces within neighborhoods. The law also stressed the conservation of natural resources and the reduction of environmental impacts by limiting urban sprawl and optimizing infrastructure.

For example, Valencia embraced these principles through the revitalization of the Cabanyal-Canyamelar district. This project involved transforming an underutilized area into a vibrant mixed-use neighborhood with improved housing, public spaces, and tourism facilities. While the initiative successfully enhanced urban density and economic activity, it also drew criticism

<footnote n="168">¹⁶⁸ The historical phenomenon of informal housing settlements, characterized by makeshift shacks or huts (known as *barracas* or *chabolas*) built by people who lacked access to formal housing. These settlements often emerged on the outskirts of cities, especially during periods of rapid urbanization in the 20th century.</footnote>
for gentrification and the displacement of long-time residents, reflecting the challenges of balancing densification with social equity.

In 2007, the EU further strengthened these ideas with the adoption of the **Leipzig Charter on Sustainable European Cities**. This document emphasized the importance of compact urban development, mixed-use neighborhoods, and the integration of sustainable transport systems. These principles were implemented, for example, in Zaragoza as part of the city's preparation for Expo 2008. The transformation of the Ebro River area focused on creating high-density housing, public spaces, and integrated transportation infrastructure. The project successfully enhanced urban connectivity and increased population density in previously underutilized areas. However, some parts of the development struggled with long-term occupancy after the Expo, highlighting the importance of sustained economic activity to support densification efforts.

Building on these foundations, Spain introduced the **National Housing and Land Use Plan in 2011**. This plan promoted urban regeneration, the reuse of underutilized land, and the development of high-density housing to address growing population demands. Bilbao's Zorrotzaurre redevelopment exemplified this approach by transforming a semi-abandoned industrial peninsula into a thriving mixed-use urban area. The project prioritized affordable housing, commercial spaces, and sustainable infrastructure, creating a model for urban regeneration in Spain. This initiative significantly increased the availability of housing and public amenities, although some challenges related to environmental remediation and funding complexities emerged during the process (Radovanović and Perović 2024).

The launch of the **EU Urban Agenda in 2016** marked another pivotal moment, emphasizing sustainable urbanization and compact city models as central pillars of European urban planning strategies. Madrid aligned its planning efforts with this agenda by implementing transit-oriented development (TOD) initiatives, focusing on areas around major transport hubs like Chamartín. The city's TOD projects encouraged high-density, mixed-use developments that improved public transit accessibility and reduced reliance on private vehicles. These efforts supported Madrid's goals of reducing carbon emissions and enhancing urban mobility. However, rising property values near these hubs raised concerns about affordability for lower-income residents, underscoring the need for equitable housing policies within densification efforts.

In 2019, the **Climate Change and Energy Transition Law** linked densification with climate resilience by promoting urban models that reduce greenhouse gas emissions through efficient land use and infrastructure. The city of Seville applied these principles by creating green urban corridors that connected dense urban neighborhoods with parks and natural areas. These corridors incorporated bicycle lanes, pedestrian pathways, and public transit stops, reducing car dependency and improving overall urban livability. While the initiative was widely appreciated for enhancing environmental quality and promoting active mobility, some residents expressed concerns about the need for more extensive public transit options to support growing populations.

The **Strategic Urban Agenda 2030**, approved in 2021 at National level, reinforced compact city models and smart growth strategies, integrating environmental, economic, and social
objectives into densification efforts. Barcelona's Superblock program became a flagship initiative under this agenda, with cities around the world aiming to replicate the initiative as to integrate green space within densification projects (Eggimann 2022). Superblocks consolidate traffic into perimeter streets, creating pedestrian-friendly internal areas with green spaces and community-oriented facilities. This approach significantly reduced air pollution, improved public health, and enhanced the quality of life for residents. However, it faced resistance from some car users and local businesses who relied on vehicle access, highlighting the challenge of balancing diverse urban priorities. Furthermore, Barcelona's Superblocks may contribute to green gentrification as the transformation of urban spaces into pedestrian-friendly, green environments can increase property values, attracting wealthier residents while displacing lower-income and historically marginalized communities, thereby reinforcing social inequalities (Anguelovski et al. 2023).

Finally, the **revision of the EU Territorial Agenda in 2023** strengthened the focus on urban density for sustainability. Valencia integrated these principles through its Valencia Smart City initiative, which emphasized energy-efficient buildings, smart grids, and IoT-based urban management in high-density zones. These projects improved energy efficiency, reduced waste, and showcased Valencia as a leader in smart urban growth – playing a role in the city being awarded the title the 2024 European Green Capital. However, the substantial investment required for such advanced technologies has posed challenges for scalability and equitable access for all residents (Mahmoud and Wael 2019).

Densification policies are increasingly tied to broader environmental and energy goals, as reflected in national climate planning. The Integrated National Energy and Climate Plan (NECP 2021–2030) explicitly promotes compact urban form and transit-oriented development as tools to reduce emissions from transport and buildings. The Climate Change and Energy Transition Law requires urban plans to integrate climate adaptation and mitigation criteria, further aligning densification with energy and greening policies. Moreover, densification is linked to energy retrofitting strategies (e.g., through the PREE program) by targeting dense areas for energy-efficient redevelopment, and to NbS initiatives like green corridors and superblocks, which often support both climate goals and higher density use of space.

This progression illustrates how Spain's densification strategies have been shaped by a combination of national priorities and EU directives. Each milestone not only pushed forward the country's approach to urban planning but also laid the groundwork for future initiatives, creating a cohesive and adaptive national policy framework which continues to impact localized (re)development projects throughout the country's 17 autonomous communities.

## 6.2 The implementation process

Spain's densification policies are implemented through a mix of legislative tools, financial programs, and planning instruments. The implementation process reflects a multi-pronged approach to addressing urban challenges while promoting sustainability and economic growth. An overview of these elements is provided below.
Urban Planning Legislation and Climate Integration

The Urban Planning Law of 2000 was the first foundational legislation establishing legal frameworks to encourage compact city development, urban renewal, and efficient land use. The law guided local governments to combat urban sprawl by prioritizing infill development and repurposing existing urban spaces. For instance, Valencia's El Carmen neighborhood revitalization utilized these principles by transforming an aging urban district into a high-density, mixed-use area with 'modern' amenities. This project preserved the historic character of the neighborhood while introducing efficient land-use practices, fostering economic growth, and increasing housing availability. However, the focus on economic revitalization often led to gentrification, displacing low-income residents and reducing the social diversity that made the neighborhood unique, through an influx of tourists and the touristification of the area (El Español, 2024).

The Climate Change and Energy Transition law of 2019 connected urban densification to Spain's climate goals by emphasizing compact urban models to reduce greenhouse gas emissions. It highlighted the integration of renewable energy systems, green roofs, and energy-efficient infrastructure in high-density areas. For example, in Vitoria-Gasteiz, green infrastructure initiatives were incorporated into urban densification projects, including the development of urban gardens and green roofs on residential buildings. These measures not only reduced energy consumption but also enhanced urban livability and resilience to climate change.

National Subsidies and Urban Regeneration Programs

Subsidies, coming from both the national government and local government sources, for urban regeneration, such as those found in programs such as the Plan Estatal de Vivienda (State Housing Plan), offer financial incentives to developers for undertaking infill development and repurposing unused urban spaces. In Bilbao, subsidies from the national government, the Basque Regional Government and the Bilbao City Council, were instrumental in transforming the Zorrotzaurre peninsula, where abandoned industrial areas were redeveloped into a vibrant urban quarter. The subsidies reduced financial barriers, enabling the development of affordable housing and public spaces while attracting private investment. However, these efforts have often prioritized economic growth over social equity, with affordability initiatives failing to meet the needs of the lowest-income households, exacerbating housing inequality in regenerated areas (Bilbai Hiria, 2024).

EU Co-Financing and Structural Funds

Structural and cohesion funds from EU, such as those from the European Regional Development Fund (ERDF), the European Social Fund (ESF), the Cohesion Fund, and NextGenerationEU funds, have also significantly supported Spain's urban densification initiatives. These funds have co-financed major projects in metropolitan areas across Spain, facing housing shortages – including Madrid, Barcelona, Valencia, Seville, Bilbao, Malaga, Zaragoza, Alicante, Castellón, Vigo, Santander, Oviedo, Murcia, and Palma de Mallorca. The Barcelona Superblock program, a celebrated and globally recognized initiative, benefited from EU funding to reconfigure traffic patterns, expand pedestrian zones, and increase urban
density without compromising sustainability. This initiative demonstrated the potential of EU funds to create transformative urban projects with long-term benefits.

## Task Incentives and Fiscal Tools

Tax reductions have also been implemented to encourage developers to focus on high-density housing projects and retrofitting existing urban infrastructure. In Madrid, developers received tax benefits — including reductions in the Impuesto sobre Construcciones, Instalaciones y Obras (ICIO) — for projects located near major public transport hubs, which helped promote compact, transit-oriented development. These fiscal tools were designed to reduce upfront development costs and improve the financial viability of high-density, sustainable housing.

Some municipalities have also introduced property tax (IBI) reductions for renovated buildings that meet energy performance or urban integration criteria. This has proven especially effective in medium-sized cities like Zaragoza and Valencia, where local governments actively promote the reuse of existing urban land rather than expansion into peripheral areas. While these tax policies help catalyze urban regeneration and densification, critics argue that their application often lacks social targeting, risking the promotion of market-rate development that are unaffordable for low- and middle-income households (Bouzarovski et al., 2018).

## Local Plans and Zoning Reforms

Localized densification plans within cities have guided urban development in cities like Barcelona and Madrid, prioritizing transit-oriented development (TOD), mixed-use neighborhoods, and efficient public spaces. The Madrid Nuevo Norte project exemplifies this, integrating residential, commercial, and transit infrastructure within a compact area. By aligning urban growth with public transit, the project aimed to minimize reliance on private vehicles and promote sustainable mobility. However, critics highlight that the prioritization of high-end commercial spaces and luxury housing often marginalizes low-income populations, who are unable to access these benefits.

Incentivized zoning reforms have encouraged higher-density housing near transit corridors and employment hubs. For example, Seville introduced zoning incentives to facilitate residential development near its metro lines, increasing population density while reducing urban sprawl. These reforms simplified approval processes, making it easier for developers to invest in high-density projects. Still, these zoning changes frequently favor upscale developments, further displacing economically vulnerable groups who cannot afford the new housing stock.

<table><thead><tr><td>Element</td><td>Description</td></tr></thead><tbody><tr><td>Legislative measures</td><td>Climate Change and Energy Transition Law (2021), Technical Building Code (2006, updated periodically)</td></tr><tr><td>Financial Support</td><td></td></tr></tbody></table>
<table><caption>Table ES16. Implementation Process (Densification)</caption>
   <tr>
    <td>
    </td>
    <td>
     Subsidies (e.g., PREE), tax incentives, regional programs (e.g., Asturias' energy efficiency subsidies)
    </td>
   </tr>
   <tr>
    <td>
     Supportive programs
    </td>
    <td>
     One-stop shops, training and certification programs
    </td>
   </tr>
   <tr>
    <td>
     Time horizon
    </td>
    <td>
     NECP 2021-2030 outlines a 10-year strategy with interim targets
    </td>
   </tr>
   <tr>
    <td>
     Assessment mechanisms
    </td>
    <td>
     Regular monitoring and reporting to evaluate progress and adjust strategies as needed
    </td>
   </tr>
   <tr>
    <td>
     Challenges and controversies
    </td>
    <td>
     Financial constraints post-2008 crisis, regulatory changes causing uncertainty, low public awareness and engagement
    </td>
   </tr>
  </table>

6.3 Size and role of the market

The densification market in Spain is influenced by various policy frameworks, financial mechanisms, and private sector participation. These elements interact in complex ways to shape urban development trends, particularly in high-density cities. Understanding how each component functions requires a deep dive into the legislative, economic, and social factors driving the urban densification process, as well as the role of public and private actors in these developments.

Vertical Housing and Private Development

Private developers have historically played a critical role in shaping the densification landscape in Spain, particularly in urban centers such as Madrid, Barcelona, Valencia, and Bilbao. These cities have experienced substantial population growth, urban migration, and increased demand for affordable housing, which has driven the need for high-density housing solutions. As Spain's cities have become more populated, urban planning policies have encouraged the construction of vertical housing—such as apartment buildings and mixed-use developments— in the heart of urban areas.

There have been several key legislative influences in this regard. The Ley General de Ordenación Urbana (1975) and its subsequent revisions, like the Ley del Suelo (1992), set the stage for high-density housing in Spain by introducing zoning laws and urban renewal initiatives that enabled developers to build more densely in cities. These laws allowed for more flexible land-use practices, enabling the vertical growth of urban spaces. The Ley de Vivienda (2022), which reaffirms the government's commitment to affordable housing, provides new incentives for the construction of high-density, low-cost housing by private developers.

Public-Private Partnerships (PPPs)

Public-Private Partnerships (PPPs) are instrumental in urban densification efforts in Spain, particularly when it comes to mixed-use developments and affordable housing projects. These partnerships allow municipalities to leverage private sector capital and expertise while fulfilling
public objectives like increasing housing stock, urban regeneration, and improving infrastructure.

Several key legislative moments have influenced the importance of PPPs in urban densification efforts in Spain. In 2017, the Ley de Contratos del Sector Público provided the legal framework for PPPs, enabling municipalities to engage private developers in projects that support urban densification and revitalization. Private developers play a crucial role in these projects, often providing the capital, expertise, and efficiency needed to deliver high-density housing and mixed-use developments, particularly in city centers and underdeveloped areas. The National Housing and Land Use Plan (2011) and Strategic Urban Agenda 2030 (2021) further encourage collaboration between public and private sectors by offering various incentives, such as tax breaks, density bonuses, and fast-tracked permits for projects that meet specific sustainability and affordability criteria. These plans create more transparent pathways for joint ventures, incentivizing developers to prioritize urban regeneration and sustainable growth, and to incorporate green infrastructure, affordable housing, and mixed-use spaces in their projects.

In Valencia, a notable example of a PPP-driven project is the regeneration of the Old Turia Riverbed, where public land has been revitalized with private investment to create mixed-use spaces, residential areas, and recreational zones. Similarly, Madrid's operation "Madrid Río" transformed the Manzanares River area into a green space while incorporating affordable housing, thanks to a successful public-private collaboration.

Market Instruments: Tax Bonuses, Density Incentives, and Land Readjustment

Several market interventions are designed to facilitate urban densification and encourage private sector involvement. These include tax incentives, density bonuses, land readjustment schemes, and innovative financing models, such as green bonds, that promote sustainable development.

Tax incentives and density bonuses are increasingly common in urban centers, particularly for developers who meet sustainability and affordability criteria. For instance, the Madrid City Council offers density bonuses in exchange for including a certain percentage of affordable housing in development projects. Similarly, Barcelona has incentivized the construction of energy-efficient buildings and increasing density by offering tax rebates and expedited permitting processes.

In densely populated urban areas, land availability is often scarce. **Land readjustment schemes**, which allow for the consolidation of fragmented plots, enable more efficient development. These schemes function as a **market mechanism** because they rely on **private landowners and developers** to drive urban transformation, with the government acting as a **regulator rather than a direct investor**. Instead of expropriating land, municipalities facilitate **land pooling**, allowing private owners to consolidate their plots for redevelopment. This process **raises property values**, enabling landowners and developers to profit while financing infrastructure improvements, making it a **self-sustaining model**. By shifting costs to the private sector and letting the market dictate redevelopment, land readjustment promotes **densification without heavy state intervention**, aligning public planning goals with market-
driven urban renewal. These schemes are particularly prevalent in Barcelona, where urbanization policies prioritize land consolidation to create denser, mixed-use neighborhoods that balance residential, commercial, and green spaces.

Green Financing and Investment Tools

In recent years, financial institutions in Spain have been increasingly focusing on sustainable urban development through mechanisms like green bonds and other forms of green financing.
This aligns with Spain's push for more sustainable cities and the EU's Green Deal. In particular, banks and financial institutions have begun offering specialized loans for energy-efficient buildings and low-carbon infrastructure, which has made high-density development more viable for developers committed to sustainability.

6.4 The multi-level governance process

Spain's densification efforts involve coordination across national, regional, and local levels, with each tier of government playing a crucial role in ensuring that policies are effectively implemented. Effective governance is essential to harmonize diverse policy objectives and ensure that densification meets both national goals and local needs.

At the national level, the Ministry of Transport, Mobility, and Urban Agenda (MITMA) plays a leading role in developing strategic frameworks such as the Urban Agenda 2030. MITMA is also responsible for overseeing the allocation of national and EU funds to densification projects, ensuring that resources are distributed efficiently to achieve the country's urban development goals. In particular, the National Housing and Land Use Plan (2011) outlines clear priorities for sustainable urban development, offering financial incentives for projects that align with densification and urban regeneration efforts. Moreover, MITMA's policies emphasize the importance of compact, sustainable cities, helping to guide local and regional efforts to reduce urban sprawl and enhance environmental sustainability.

**The National Housing Observatory**, a key governmental body, monitors housing trends across Spain. This body collects data, conducts research, and provides valuable insights that inform densification policies and address emerging challenges. By tracking housing demand, supply, and affordability, the Observatory plays an instrumental role in shaping policies that respond to shifting urban dynamics.

At the regional level, autonomous communities are granted significant regulatory autonomy, allowing them to adapt national policies to suit local contexts. This flexibility enables each region to address specific needs and challenges unique to its urban environments. For example, Catalonia has introduced regional legislation to promote transit-oriented development (TOD), encouraging high-density housing near public transportation hubs to reduce car dependency and improve urban mobility. Similarly, Andalusia has focused on revitalizing historic urban cores, combining preservation with densification efforts to breathe new life into older neighborhoods while addressing housing shortages.

Municipalities are the key actors in implementing zoning, urban planning, and permitting processes. They are responsible for the ground-level application of densification policies, often
working in collaboration with both regional and national authorities to align local projects with broader strategic goals. Local governments also engage directly with communities to ensure public support for densification initiatives. In some cases, municipalities offer incentives to developers to ensure that projects meet local housing needs, such as including affordable units in new developments.

Private developers play a crucial role in these projects, delivering high-density housing that aligns with local zoning and urban planning policies. By providing capital and expertise, private developers help municipalities meet their densification goals. The National Housing and Land Use Plan (2011) and the Strategic Urban Agenda 2030 (2021) have offered developers a framework of incentives to prioritize sustainable and affordable projects, such as tax breaks, density bonuses, and green building certifications.

<table><thead><tr><td>Actor</td><td>Type</td><td>Scale</td><td>Domain</td><td>Role</td><td>Policy Effect</td></tr></thead><tbody><tr><td>Ministry of Transport, Mobility and Urban Agenda</td><td>Public</td><td>Central/National</td><td>Political</td><td>Sets national strategy for urban planning and densification</td><td>Frames densification priorities, allocates funding</td></tr><tr><td>Ministry for the Ecological Transition (MITECO)</td><td>Public</td><td>Central/National</td><td>Technical/Political</td><td>Aligns urban form with climate targets (energy, mobility, land use)</td><td>Encourages sustainable, low-carbon urban models</td></tr><tr><td>National Housing Observatory</td><td>Public</td><td>Central/National</td><td>Technical</td><td>Provides data and analysis to support housing policy development</td><td>Informs evidence-based planning and densification monitoring</td></tr><tr><td>Autonomous Communities (e.g., Catalonia)</td><td>Public</td><td>Regional</td><td>Political/Technical</td><td>Tailor national frameworks, coordinate zoning and subsidies (e.g., TOD projects)</td><td>Localize densification tools to specific challenges</td></tr><tr><td>INCASÒL (Catalonia)</td><td>Public</td><td>Regional</td><td>Technical</td><td>Facilitates land readjustment and urban redevelopment</td><td>Unlocks land for densification, especially in brownfield sites</td></tr><tr><td>Municipalities / Local Governments</td><td>Public</td><td>Local</td><td>Political</td><td>Implement planning regulations, issue permits, and engage communities</td><td>Control the pace and location of densification</td></tr><tr><td>EU Institutions / Funding (e.g., ERDF, NextGenEU)</td><td>Public (Supranational)</td><td>EU</td><td>Political/Technical</td><td>Fund urban regeneration, promote green densification</td><td>Provide incentives for compact, sustainable development</td></tr></tbody></table>
<table><caption>Table ES17. Key Actors and their Roles (Densification)</caption><tr><td></td><td></td><td></td><td></td><td>through strategic agendas</td><td></td></tr><tr><td>ICO (Instituto de Crédito Oficial)</td><td>Public</td><td>National</td><td>Technical</td><td>Provides affordable public financing to urban development and densification projects</td><td>Lowers financial barriers for socially oriented densification</td></tr><tr><td>Private Developers</td><td>Private</td><td>Local/National</td><td>Technical</td><td>Design and build high-density housing and mixed-use projects</td><td>Shape built environment, often guided by market logic</td></tr><tr><td>Banks / Real Estate Funds</td><td>Private</td><td>National/EU</td><td>Technical</td><td>Provide investment capital, especially for large redevelopment projects</td><td>Influence what types of projects get built and where</td></tr><tr><td>Civil Society Organizations / Housing NGOs</td><td>Civil Society</td><td>Local/National</td><td>Political</td><td>Advocate for affordable, inclusive urban development; monitor exclusionary trends</td><td>Pressure for equity, transparency, and anti-displacement safeguards</td></tr><tr><td>Community Associations / Neighborhood Groups</td><td>Civil Society</td><td>Local</td><td>Political</td><td>Represent resident concerns, especially in areas targeted for densification</td><td>Enable participatory planning, resist unwanted gentrification or displacement</td></tr></table>

## 6.5 Achievements, assessments, and challenges

The compact city model has helped curb urban sprawl, preserving green spaces and aligning with EU sustainability goals. Cities like Madrid and Barcelona have prioritized infill development, converting underutilized areas into high-density, mixed-use neighborhoods that minimize outward expansion. Transit-Oriented Developments (TODs), particularly in Madrid and Valencia, have improved accessibility, reduced car dependency, and contributed to EU mobility targets.

Economically, densification has revitalized local economies, attracting businesses and boosting property values. Cities like Bilbao and Seville have seen increased tourism and service industry growth, alongside infrastructure upgrades. However, higher-density developments often drive up property values and rents, reducing affordability for lower-income residents. Gentrification in Barcelona and Madrid has underscored the need for policies like the Ley de Vivienda (2022) to protect vulnerable populations from displacement.
Infrastructure strain remains a challenge. Rapid densification can overwhelm public services, causing congestion and service bottlenecks. Valencia, for example, has expanded housing availability but faces growing pressure on waste management and transportation. Strategic planning and investment are crucial to maintaining livability.

Densification has not been evenly implemented, deepening regional disparities. While Barcelona and Madrid lead in urban transformation, rural and peripheral areas like Castilla-La Mancha struggle to keep pace, leading to unequal access to housing and services. Key Performance Indicators (KPIs), utilized by governments, such as population density, housing affordability, and land-use efficiency help monitor these efforts.

Periodic policy reviews, like those assessing Barcelona's Superblock program, aim to refine strategies, yet wealthier districts tend to receive more resources, perpetuating inequality. Public opposition to densification, often driven by concerns over overcrowding and gentrification, highlights the need for inclusive, participatory planning. However, marginalized groups often lack meaningful involvement in decision-making processes.

Regulatory hurdles, including bureaucratic delays and conflicting local policies, further slow densification efforts. High land costs in cities like Madrid and Barcelona deter private investment in central areas, sometimes pushing development to peri-urban zones, inadvertently encouraging sprawl.

From an environmental justice perspective, densification supports sustainability by reducing per capita carbon emissions and enhancing public transit. However, if not carefully managed, it can exacerbate social inequities. In Madrid, the rise of luxury developments in areas like Malasaña and Lavapiés has displaced lower-income residents, highlighting the need for a balanced approach that integrates affordability with sustainable urban growth.

<table><thead><tr><td>Impact area</td><td>Measured potential or</td><td>Description/evidence</td></tr></thead><tbody><tr><td>Socio-spatial exclusion</td><td>Measured</td><td>High-density redevelopment displaces low-income residents in city centers (e.g., Madrid Río, Barcelona Superilla) (Anguelovski et al., 2023).</td></tr><tr><td>Affordability pressures</td><td>Measured</td><td>Rising land values in densified areas make inclusion of affordable housing difficult without regulation (Zorrotzaurre, Bilbao; Policy Lab 2025).</td></tr><tr><td>Limited inclusion of social housing</td><td>Measured</td><td>Densification programs often lack binding quotas for affordable units (Strategic Urban Agenda 2030).</td></tr><tr><td>Inequitable TOD development</td><td>Potential</td><td>Transit-oriented projects risk prioritizing market-value housing without enforceable inclusionary zoning (Interview with academic planner).</td></tr></tbody></table>
<table><caption>Table ES18. Measured and Potential Impacts on Housing Equality (Densification)</caption><tr><td>Displacement through upgrading</td><td>Measured</td><td>Combined infrastructure and densification projects indirectly displace existing low-income communities (Bouzarovski et al., 2018).</td></tr><tr><td>Opportunity for vertical equity</td><td>Potential</td><td>Emerging regional practices (e.g., Catalonia's INCASÒL) integrate safeguards and land readjustment for more inclusive outcomes.</td></tr></table>

# 7 Summary and discussion of results

Spain has successfully implemented **energy retrofitting programs**, improving the sustainability and efficiency of its building stock. The **FREE program** and **tax incentives** have encouraged energy-efficient renovations, particularly in aging urban areas. However, **regional disparities in implementation** persist, with wealthier regions benefiting more from subsidies than economically disadvantaged areas. Furthermore, **gentrification concerns** have emerged as retrofitting often leads to higher property values, pushing lower-income residents out of renovated areas.

Spain has made significant strides in implementing **urban greening projects**, with cities like **Barcelona**, **Valencia**, and **Vitoria-Gasteiz** leading the way. Benefits include **improved air quality, climate adaptation, and biodiversity conservation**. However, the **lack of a dedicated national budget for NBS** means that funding remains heavily dependent on **EU grants and local government initiatives**. Additionally, the phenomenon of **green gentrification** has raised concerns, as improved green spaces tend to increase property values and attract wealthier demographics, potentially displacing long-term residents.

Densification has been a **key strategy** in Spain's urban sustainability agenda, with policies aimed at **curbing urban sprawl and integrating public transit with high-density developments**. Projects such as **Madrid Nuevo Norte** and **Barcelona's Superblock initiative** have reshaped urban landscapes, reducing car dependency and improving environmental sustainability. However, densification has also led to **rising housing costs**, making affordability a significant challenge. **Regulatory inefficiencies and fragmented governance** have further slowed the implementation of high-density developments, particularly in economically weaker regions.

Spain's environmental and energy policies are shaped by overlapping economic, normative, institutional, and contextual factors at both national and local levels. Spain's highly decentralized governance system plays a central role: while national frameworks (e.g., NECP, Climate Law) establish broad objectives and legal parameters, implementation is largely delegated to autonomous communities and municipalities. This often leads to uneven uptake, administrative capacity, and funding absorption, particularly between wealthier and less-resourced regions. Economically, the structure of incentives—co-financing requirements, tax rebates, density bonuses—favors actors with access to capital, contributing to unequal participation in retrofit and densification schemes. Normatively, the strong focus on sustainability and urban innovation in public discourse often coexists with conflicting market
logics, where private developers prioritize profitability over affordability or equity. Institutionally, EEPs are fragmented across different ministries and levels of government, creating coordination gaps, while local authorities often rely on EU or national funds to act. Finally, contextual factors such as the ageing housing stock, high rates of homeownership, and growing social inequality directly shape how policies are received, contested, and adapted on the ground.

One important avenue for mitigating displacement risks associated with green infrastructure and urban renewal is the expansion of social and other forms of decommodified housing. While Spain's social housing stock is currently limited, particularly in rental form, there is growing recognition among experts and policymakers that ensuring affordability and tenure security must accompany green urban transitions. Interviews with housing professionals and public officials emphasized that retrofitting and urban regeneration, when driven primarily by market actors, tend to favor middle- and upper-income groups. Embedding affordability conditions into green redevelopment programs, dedicating a share of upgraded housing stock to public or cooperative housing, and expanding public land banking (as seen with INCASÒL in Catalonia) are potential tools to counteract exclusionary effects. Strengthening non-market housing mechanisms could thus serve as a structural safeguard against the unintended consequences of EEPs, particularly in gentrifying neighborhoods undergoing green and dense redevelopment.

While Spain has made substantial progress in **retrofitting**, **NBS implementation**, and **densification**, **socio-economic inequalities have not been adequately addressed** in policy design. Future policy efforts should:

1. **Expand financial accessibility for low-income households to participate in energy retrofitting programs.**

Current retrofit programs, such as PREE, often require high upfront co-financing and complex application processes, which create barriers for vulnerable groups. Policy revisions should include simplified procedures, targeted subsidies, and zero-interest financing mechanisms to ensure equitable access and prevent the exclusion of those most in need of energy efficiency improvements.

2. **Mitigate displacement risks associated with green infrastructure and urban renewal projects.**

Green interventions can inadvertently trigger rent increases and gentrification in upgraded neighborhoods. Urban sustainability policies must incorporate displacement risk assessments, tenant protections, and participatory planning approaches to ensure long-term residents are not pushed out as a result of environmental improvements.

3. **Integrate affordability protections into green renewal policies.**

Social housing and decommodified housing instruments should be used to anchor affordability within areas undergoing energy retrofits, greening, or densification. Mandating affordable housing quotas and supporting cooperative and public housing models can help align environmental objectives with long-term social equity goals.

4. **Improve governance coordination across national, regional, and municipal levels.**
Spain's multilevel governance system leads to fragmented implementation and uneven access to funding and technical resources. Stronger coordination mechanisms, standardized frameworks, and shared learning platforms are needed to reduce administrative gaps and support consistent policy uptake across regions and cities.

5. Prioritize affordability in densification efforts to ensure that urban sustainability does not come at the cost of social equity. Urban compactness strategies must be tied to clear affordability objectives, especially in high-demand areas. Densification policies should require affordable housing components, incentivize mixed-income development, and monitor socio-spatial impacts to avoid exacerbating existing inequalities.

By refining these approaches, Spain may be able to reach their sustainability goals in a more just
manner.

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NATIONAL REPORT ON THE REGULATORY SYSTEM OF
EEPs IN SWITZERLAND

# 1 Executive Summary

This report aims at providing an analysis of Switzerland's environmental and energy policies, with a focus on energy renovations of residential housing, densification and nature-based solutions (NBS). It is primarily based on an in-depth review of policies and regulations, which are analysed through a multi-level governance lens. In addition, interviews were conducted with state ministry representatives, with experts from national and cantonal organisations, the private sector, and academia. The report also includes some preliminary reflections on their implications on housing inequality.

Chapter 1 provides a general introduction. It is followed by chapter 2, which focuses on Switzerland, a small and wealthy country with a population of only about nine million. Historically, the favourable economic situation and employment opportunities have attracted large numbers of migrants, leading to a steady population growth. The country is governed under a federal system at three levels: the Confederation, the 26 cantons and the 2,172 municipalities. Being characterised by a direct democracy, Switzerland provides extensive opportunities for political participation. Over the last decades there have been dozens of popular initiatives and referenda related to housing, energy and the environment, clearly reflecting the importance of these topics in public debates.

Switzerland is a country of tenants with the lowest homeownership rate in Europe. Only 35.9% of dwellings are owner-occupied. High housing prices and the liberal rental housing market that contribute to making investments in the rental sector profitable are among the reasons given for this situation. Apartment buildings constitute the majority of the rental housing stock. They are primarily owned by private individuals, private companies and pension funds. Public- and non-profit cooperative housing play an important role in some cities, but a relatively marginal one at national level.

Chapter 3 focuses on Switzerland's energy policy with particular focus on energy retrofitting of residential buildings. The Swiss government's commitment to the 1992 Climate Change Convention, the Kyoto Protocol and the Paris Agreement resulted in the passing of the CO2 Act in 2000. This Act mandated a 10% reduction in CO2 emissions by 2010. It also includes a provision for a CO2 levy on fossil fuels used for heating, lighting, or electricity generation that was introduced in 2008. In 2010 Switzerland launched the Buildings Programme, which provides financial incentives for energy-efficient renovations. The programme is being implemented and is co-financed by the cantons. Concerns that energy refurbishments are contributing to the loss of affordable housing have started to emerge as costs related to property improvements—such as energy refurbishments—can be passed on to tenants in the form of rent increases.

Chapter 4 focuses on nature-based solutions (NBS). Until recently Switzerland did not use the term NBS and related policies are integrated in those focusing on biodiversity conservation,
climate change adaptation, and river restoration. In 2012 the Federal Council released the first part of its Climate Change Adaptation Strategy, which proposes enhancing green infrastructure, promoting open spaces, preventing soil sealing, and using green and shaded areas to mitigate heatwave impacts and river restoration. The 2014 Action Plan emphasized the importance of spatial planning in adapting urban areas to increasing heat stress. Municipalities, supported by cantons and federal offices, were tasked with implementing climate change adaptation and mitigation measures, with limited funding coming from the federal government. As a result, only few cities are currently programmatically implementing NBS, while smaller towns often lack a clear strategy.

Chapter 5 focuses on densification, which has been a key policy goal in Switzerland since the 2014 revision of the Spatial Planning Act, when densification became legally binding. However, the implementation of densification objectives has been rather slow as the principle of subsidiarity grants significant authority to local governments. In fact, a significant portion of new housing continues to be built on undeveloped land, particularly in rural and peri-urban areas. This trend is gradually shifting, especially in cities and tourist regions, where the combination of restrictive building zones and low interest rates has sparked a construction boom and driven up land prices. One of the key challenges of densification is its impact on housing affordability. In fact, between 2000 and 2021, the price of single-family houses increased by 80%, while rents rose by 30%. Currently, no policies specifically address the social impacts of densification. Most strategies focus on spatial issues, while socioeconomic consequences like displacement and unequal housing conditions are largely overlooked.

## 2 Introduction and methodology

This report aims at providing a qualitative analysis of Switzerland's environmental and energy policies, with some preliminary reflections on their implications on housing inequality. The report is based on an in-depth review of policies and regulations and eight interviews, which are analysed through a multi-level governance lens. Switzerland is not part of the EU but shares the same climate goals. The strategies towards these goals, however, are defined by national and cantonal policies, with cantons and municipalities enjoying a high degree of autonomy. Switzerland is characterised by a direct democracy; its citizens can and do exercise a strong influence on environmental and energy policies through popular initiatives or referenda. While there is an overall consensus on climate goals, the strategies towards attaining them are constantly being challenged as reflected by numerous popular initiatives, often followed by federal government's counter proposals.

The report focuses on three specific domains that are expected to play a key role in the adaptation and mitigation of climate change: energy renovations of residential buildings, densification, and nature-based solutions (NBS).

Energy efficient retrofitting includes the building envelop and the engineering system, including the replacement of windows and heating systems. In Switzerland, these measures are strongly incentivized and subsidized through the Buildings Programme (Gebäudeprogramm).

Densification emerged as a concept at a global level in response to the environmental debates of the 1960s and 1970s (Burgess, 2000). Advocacy for 'compact cities' aimed at transforming
urban settlements to enhance their environmental sustainability by reducing land consumption, limit commuting, and slow down urban sprawl. In Switzerland, a small and mountainous country characterised by the scarcity of buildable land and the desire for a high degree of self-sufficiency in food production, a parsimonious land use has been the main concern of spatial planning for several decades. But only since 2014 densification has become a legally binding objective for the whole country.

NBS is a term increasingly used in policy and academic circles to refer to actions that are inspired by, supported by, or copied from nature with the aim to increase urban sustainability and to improve the resilience for humans and biodiversity (European Commission: Directorate-General for Research and Innovation, 2015). NBS often aim to address climate change mitigation and/or adaptation and to combat biodiversity loss. This implies the protection, restoration, and/or management of natural and semi-natural ecosystems, management of productive land and coastal areas, and the creation of new “green” or “blue” infrastructures. In Switzerland, the concept of NBS appeared in policy documents only recently, but public concerns, political debates, popular initiatives, and local-level projects that may be labelled as NBS are not new. However, national level policies to promote NBS are rather weak with initiatives depending entirely on municipal governance. Moreover, while public debates, political concerns, and scientific literature over the negative impact of energy refurbishments and densification on an equitable and affordable access to housing in Switzerland are not new, so far links between NBS and housing inequality trends have not been explored and debated yet.

This report is based on the review of secondary data, such as information, data, thematic studies, and evaluation reports available on the website of relevant governmental agencies (e.g. those of the Federal Office of Housing, the Federal Office of Spatial Development, the Federal Office of Energy) and those related to specific programmes such SwissEnergy (EnergieSchweiz) and the Buildings Programme. In addition, interviews with experts from the public and private sector and academia provided insights into legislation, multi-level governance processes and the implementation of regulations. To this aim, we spoke with representatives of the SFOE, the SFOSD, the FOEN, the EnDK, EspaceSuisse, ETH SPUR, Grünstadt Schweiz and LemonConsult (see appendix). Moreover, the subjects were discussed at a PolicyLab attended by 28 participants, resulting in the provision of additional information (see appendix). Longitudinal Information on popular initiatives, direct and indirect counter-proposal and legal frameworks related to environmental and energy policies could be found on the official website of the Federal Council. As will be discussed in the following chapters, Switzerland is a federal state with its 26 cantons and 2'172 municipalities, which enjoy a high degree of autonomy, with considerable implications on the specific modalities and progress in the implementation of environmental and energy policies. These are affected by several factors, such as context specific concerns and interests, the economic situation and the overall political orientation.

The report aims at providing an overview of national policies and the system through which they are being implemented. However, it was beyond its scope to analyse the specific environmental and energy policies of each canton and municipality. Finally, the report is also based on a review of scientific literature, in particular related the impact of environmental and energy policies on housing inequality. Such literature remains relatively limited and focuses
primarily on the impact of densification in and around Switzerland's main cities (Zurich, Basel and Geneva), with only limited studies on other regions and cities. Publications on the impact of energy refurbishments on housing equity, with few exceptions, is almost exclusively limited to some research projects commissioned by Federal Office of Housing, while we could not find any scientific publication focusing on NBS and its interlinkage with sustainable and inclusive housing in Switzerland.

# 3 Switzerland: main socio-economic characteristics and governance system

## 3.1 Switzerland's socioeconomic profile

Switzerland is a small country with a size of only 41,285 km² and a population of approximately 9 million people. With the Alps occupying two thirds of its territory, but housing only 10% of the population, the country is facing a considerable pressure on its scarce land resources (EDA, 2024). Indeed, about 2/3 of Switzerland's population live in the Swiss Plateau region, which covers only 30% of its surface. 84.8% of the country's inhabitants live in areas classified as urban (BFS, 2024d).

With an annual GDP per capita of USD 92'000 in 2022 Switzerland ranks as one of the top 10 economies worldwide. Approximately 74% of Swiss GDP is generated by the services sector, 25% by industry and less than 1% by the agricultural sector (FDFA, 2024a).

Switzerland has one of the lowest unemployment rates in Europe (2.0% in 2023; Staatssekretariat für Wirtschaft SECO, 2024) and is actually experiencing a labour shortage in many sectors (Jaberg, 2024; O'Sullivan, 2024). The monthly median gross salary for full-time employees in 2020 amounted to CHF 6'665. However, there is a significant discrepancy between the salaries of lower- and higher paid jobs. In fact, the lowest-paid 10% of employees earned less than CHF 4,382 gross per month, compared with over CHF 11,996 gross per month for the highest-paid 10% (FDFA, 2024b).

The country's favourable economic situation and employment opportunities have historically attracted large numbers of migrants, in particular from surrounding European countries. As a result, Switzerland has seen a steady population growth in the last three decades, from close to seven million inhabitants in 1990 to slightly over nine million in 2024 (BFS, 2024e). 40% of Switzerland's permanent resident population have a migration background, defined by the Federal Statistical Office (FSO) as "all foreign nationals and naturalized Swiss citizens, except for those born in Switzerland and whose parents were both born in Switzerland (3rd generation), as well as Swiss citizens at birth whose parents were both born abroad" (FSO, 2024).

Switzerland is not exempt of poverty; in 2022, 8.2% of the Swiss population i.e. approximately 702'000 people were affected by income poverty. Most severely affected were people living alone, single-parents with minor children, persons with no post-compulsory education, foreign nationals from Eastern Europe or non-European countries, and those living in households with no employed person. However, in 2022, also 3.8% of all employed persons in Switzerland
were affected by poverty, corresponding to 144'000 persons. Employed persons particularly affected by poverty are those who worked for only part of the year, self-employed persons, persons with a temporary contract and persons employed in small businesses (FSO, 2023).

On average, Swiss households spend 13.8% of their gross income on housing and electricity, 7.7% on transport, 6.3% on food and non-alcoholic beverages and 6.6% on compulsory health insurance (BFS, 2024c).

## 3.2 Switzerland's governance system

Switzerland is governed under a federal system at three levels: the Confederation, the 26 cantons and the 2,172 municipalities. The country is governed by the Federal Council, a seven-member collegial body whose decisions are made by consensus. Accordingly, left, right, and centrist parties all share executive power. Members of the Federal Council are traditionally drawn from the ranks of the four parties with the largest share of popular votes: the (right conservative) Swiss People's Party (SVP), the Social Democratic Party (SP), the Centre (an alliance of the Christian Democratic People's Party (CVP) and the Conservative Democratic Party (BDP)) and The Liberals (FDP). There are also parties, such as for example the Green Party and the Green Liberal Party, which are not represented on the Federal Council but have representatives in the Swiss Parliament (FDFA, n.d.). Federal councillors are elected by the national parliament, the Federal Assembly.

Each federal councillor (sometimes also referred to as minister) is assigned a department, which is further divided into several federal offices. Particularly relevant to our project is the Federal Department of the Environment, Transport, Energy and Communication (DETEC), which includes, among others, the Swiss Federal Office of Energy (SFOE) and the Federal Office for the Environment (FOEN). Equally relevant to our project is the Federal Office for Housing (FOH), under the Federal Department of Economic Affairs, Education and Research (EAER).

The Federal Assembly consists of an upper and a lower chamber. The National Council (200 members) is the lower house and represents the people. The Council of States (46 members) is the upper house and represents the cantons. Delegates from eleven different parties set forward their views in the current parliament. Switzerland has several more political parties, but some are only active at the regional level. Members of the parliament (both chambers) are elected every four years.

## 3.3 Switzerland's direct democracy and its impact on housing, energy and environmental policies

Since becoming a federal state in 1848, Switzerland has been characterised by a direct democracy providing expanded opportunities for democratic participation. Along the usual voting rights accorded in democracies, the Swiss people also have the right to launch and vote on referenda and popular initiatives. Popular initiatives allow citizens to propose changes to the Swiss Federal Constitution. If an initiative gathers enough support, it is put to a nationwide vote. To launch a popular initiative, citizens must collect at least 100,000 valid signatures from
eligible voters within 18 months. Once the required signatures are collected and verified, the initiative is examined by the Federal Assembly, which may either accept the proposal, reject it, or put forward a counter-proposal. If the initiative proceeds to a nationwide vote, it requires a double majority to pass: the majority of voters across the whole country (the popular majority) and a majority of the cantons (the cantonal majority). Each canton, regardless of its population, has one vote, so even small cantons have an equal say in the final decision. If both conditions are met, the initiative becomes law.

A counter-proposal is an alternative proposal that either modifies the original initiative or offers a different solution to the issue at hand. A counter-proposal can be presented alongside the original initiative in a nationwide vote, giving the public the option to choose between the initiative, the counter-proposal, or reject both. If the counter-proposal is accepted but the original initiative is rejected, the counter-proposal may still become law if it also receives majority support from the voters and the cantons.

Referenda are another critical component of Switzerland's system of direct democracy. Through a referendum, citizens can challenge laws or legal provisions that have already been passed by Parliament. This allows people to stop or amend legislation they disagree with. To call for a referendum, 50,000 valid signatures must be collected within 100 days after the law is passed. If enough signatures are gathered, a national vote is held, and the citizens decide whether the law should stand or be repealed. Like the popular initiative, a referendum also requires a double majority: the majority of voters and the majority of the cantons must approve the decision for it to be valid. The voting system in Switzerland ensures that both the majority of the population and the majority of cantons are involved in decision-making. This dual majority aims at protecting the interests of both larger urban areas and smaller rural regions.

Overall, Switzerland's system of direct democracy empowers citizens to influence the country's laws, ensuring that government decisions reflect the will of the people. Whether it is through a popular initiative to amend the constitution, a referendum to challenge a law, or a counter-proposal to offer an alternative solution, these mechanisms give Swiss citizens a substantial role in shaping their nation's future.

Over the last few decades issues related to housing, energy and the environment have been subject to several popular initiatives, clearly reflecting the importance of these topics in public debates. For example, in 2015, the popular initiative "More Affordable Housing" (Mehr bezahlbare Wohnungen) was launched. It aimed at making housing more affordable by promoting the construction of affordable housing, improving tenants' rights and limiting speculative practices in the housing market by introducing a right of first refusal for public authorities. The initiative was supported by the Swiss tenants' association and several progressive political groups. However, it was rejected by the majority of voters in a popular vote held in 2020.

Also launched in 2015, the popular initiative "Stopping urban sprawl - for sustainable settlement development" (Zersiedlung stoppen – für eine nachhaltige Siedlungsentwicklung (Zersiedlungsinitiative)) raised concerns about the environmental consequences of urban sprawl and demanded to further limit building zones. Due to the recent revision of the Spatial Planning Act (SPA, Raumplanungsgesetz, revised in 2014), the issue was not considered
urgent enough to convince a majority of the voters and was accordingly rejected in 2019. The
partial revision of the SPA in 2014 proposed by the Federal Council had itself been triggered
by the popular initiative "Space for Human and Nature" (Raum für Mensch und Natur
(Landschaftsinitiative)) in 2013. The original motion sought to freeze the spreading of building
zones, aiming to curb urban sprawl.

In 2003, the popular initiative "Yes to fair rents" (Ja zu fairen Mieten) aimed to tighten the regulation and contestability of rents and to improve tenants' rights. It was rejected by the electorate.

The years before the 2000s saw a number of initiatives raising demands on stricter rent control, more affordable housing, land use regulations, and measures against speculation in the housing market. For example, in 1986, the Swiss population called for an improvement of the tenant's rights with a popular initiative titled "For the legal protection of tenants" (Für den Mieterschutz), causing a counter-proposal by the federation, which was accepted in 1987. It was followed by the "Urban-rural Initiative against land speculation" (Stadt-Land-Initiative gegen die Bodenspekulation) in 1988, which addressed rising land prices, but was rejected by the voting majority.

Switzerland is a liberal-conservative country. Accordingly, progressive initiatives are typically rejected by voters. However, in some cases led to accepted counter-proposals by the government, thus nevertheless leading to some policy changes. However, because of Switzerland's system of subsidiarity, in which the responsibility for implementing federal spatial planning decisions lies with cantons and municipalities, many initiatives address issues at the local level. Housing initiatives, targets for a minimum proportion of affordable housing, and land conservation initiatives, have attempted to secure affordable housing in many municipalities. Likewise, active spatial policies are also implemented locally.

Over the years, Switzerland has also seen a significant number of popular initiatives related to a wide range of environmental issues, including climate change, conservation of natural resources, biodiversity, and pollution control. For example, the recently withdrawn "Glacier Initiative" (Für ein gesundes Klima (Gletscherinitiative)) sought to achieve net-zero carbon emissions in Switzerland by 2050, aligning the country's policies with the goals of the Paris Agreement. The Federal Council decided on an indirect counter-proposal for a new climate law (Klimagesetz), which was accepted by almost 60% of the population in a referendum in 2023. This law sets a net-zero carbon target for 2050 and mobilises subsidies for climate-neutral energy sources.

The popular initiative "For a sustainable and resource-efficient economy" (Für eine nachhaltige und ressourceneffiziente Wirtschaft (Grüne Wirtschaft)) focused on sustainable production, waste reduction, and the efficient use of resources and aimed at a better regulation of the economy on these issues. It proposed new measures to integrate environmental sustainability into economic decision-making, but was rejected by the voters in 2012.

As shown, also the initiatives aiming at a stronger climate protection, are generally rejected by
the Swiss voters but have triggered fierce public debates around these topics and in some
instances nevertheless had an influence on related policies, in particular in cases where public
support for the cause was strong.
An overview of all popular initiatives held in Switzerland between 1893 and today is provided online by the Swiss Federal Chancellery.

3.4 Switzerland’s housing system

Switzerland is a country of tenants with the lowest homeownership rates in Europe. Currently only 35.9% of dwellings are owner-occupied (Bundesamt für Statistik, 2024b). Several reasons explain this low rate of homeownership such as the very high prices of residential real estate (Bourassa & Hoesli, 2010), a relatively liberal rental housing market with a relatively weak protection of tenants (Debrunner, Kolocek, et al., 2024). These factors contribute to making investments in the rental sector profitable, even though rents can only be increased in case of a proven increase of operation and maintenance costs or interest rates (Bourassa et al., 2010, p. 270). This leads to higher investments in the construction and maintenance of rental units than in other countries, with the result that these have a quality comparable to owner-occupied housing (BWO, 2005). Furthermore, as pointed out by Bourassa et al. (2010, p. 269), income tax rules in Switzerland are not particularly favourable to home ownership due to the imputed rent system. However, the tax value of a property for wealth taxation purposes is generally significantly below its market value.

Another factor that may have contributed to the low share of homeownership is related to the fact that a legal framework for condominium ownership was introduced in Switzerland only in 1965. As a result, in urban areas characterised by a relatively old multifamily housing stock, homeownership rates remain very low (BWO, 2005).

There are significant differences in the homeownership rates between urban and rural areas. In several predominantly rural cantons more than 50% of the households own their dwelling, but the highly urbanised cantons of Geneva and Basel-City, for example, have homeownership rates of only 18.9% and 15.5% respectively. In the city of Zurich, over 90% of the households do not own the dwelling in which they reside (BFS, 2024a).

Currently, Switzerland counts close to 1.8 million residential buildings and 4.8 million dwellings (Bundesamt für Statistik, 2024c). Each year between 30'000 and 50'000 new dwellings are being built to meet the demand of a growing population and a shrinking average household size. On average each dwelling is inhabited by approximately 1.9 persons. While the per capita consumption of space in 1980 was 34 m² in 1980, it increased to an average of 46.5 m² in 2023 (BFS, 2024b).

About 18.7% of Switzerland's dwellings were built before 1919, 42.1% between 1913 and 1980 and 39% in the past 44 years, i.e. after 1980. Detached single family privately-owned houses prevail in sub-urban and rural areas. At national level, 23% of Switzerland's inhabitants live in this housing typology and another 11.2% in semi-detached or terraced houses. The majority of the rental housing stock in cities consists of apartment buildings. 37% of the country's inhabitants live in apartments buildings with less than 10 dwellings, and 25% in larger ones. Apartment buildings are primarily owned by private individuals and to a lower degree by private companies and pension funds. Public rental housing and non-profit housing owned either by cooperatives or by public and private foundations constitute a significant category of owners in some cities but play a relatively marginal role at national level. Public housing is generally subsidized and targeting socioeconomically disadvantaged households, while housing
cooperatives are committed towards non-profit and non-commodifiable housing for their members, regardless of their socioeconomic status.

Whereas most European countries define housing costs as burden when they exceed 30% of the gross income, in Switzerland a housing costs are considered a burden for lower income people when they exceed 25% of their disposable income. On average, households in Switzerland spend an average of 20% of their disposable income on housing, but for large share of lower-income people, single parents, and foreign-born households they often exceed 30% of their disposable income<fnref n="169" />.

<table><thead><tr><th></th><th>Housing</th><th>Housing Retrofitting</th><th>NBS</th><th>Densification</th></tr></thead><tbody><tr><th>National level</th><td>Responsible for the promotion of adequate and affordable housing for all<br/>Federal Office for Housing (FOH)<br/>- Financial tools for non-profit sector<br/>- Federal tenancy law</td><td>Responsible for reduction of Co2 emissions and decarbonisation<br/>Swiss Federal Office of Energy (SFOE)<br/>- Financial tools<br/>- Support and initiative for Innovation<br/>- Objectives for energy efficiency and decarbonisation</td><td>Responsible for the protection of ecologically valuable landscapes and strategies in climate adaption and biodiversity<br/>Federal Office for the Environment (FOEN)<br/>- Financial tools for pilot-projects<br/>- Objectives for biodiversity and climate adaptation</td><td>Responsible for sustainable land use and the differentiation of building- and non-building zones<br/>Federal Office for Spatial Development (SFOSD)<br/>- Laws<br/>- Objectives sustainable land take<br/>- Technical guidelines</td></tr><tr><th>Cantonal level</th><td>Responsible for the regulations, implementation and subsidy schemes<br/>- Cantonal tenancy law<br/>- Cantonal housing policy<fnref n="170" />: e.g. Subsidy programmes, promotion and consultancy, rent control)</td><td>Responsible for the regulations, implementation and subsidy schemes<br/>- Cantonal regulations and objectives<br/>- Cantonal financial tools<fnref n="171" />: e.g. Subsidy programmes, promotion and consultancy</td><td>Responsible for the implementation of national policy<br/>- Cantonal objectives<br/>- Structure planning<br/>- Ecological compensation</td><td>Responsible for the implementation of national policy<br/>- Cantonal spatial planning (regulation of building zones)<br/>- Building law (PBG)</td></tr></tbody></table>

<footnote n="169">¹⁶⁹ For details see Widmer, Hannah et al. 2024. National report on housing inequality: Switzerland ReHouIn Deliverable D2.1.</footnote>

<footnote n="170">¹⁷⁰ Housing is a cantonal competence, however only 9 out of 26 cantons have local instruments for housing promotion. These tasks and policies can therefore be considered voluntary. The same goes for municipal housing policy.</footnote>

<footnote n="171">¹⁷¹ The cantons can decide whether to promote energy retrofitting. However, they need a cantonal subsidy programme to access federal contributions. Also, municipal programmes are voluntary</footnote>
<table><caption>Table CH1. The organisation of competences for ecological transitions and housing policies at different governance levels.</caption><thead><tr><th></th><th>Responsible for the implementation of cantonal policy and additional local policy</th><th>Responsible for the implementation of cantonal policy</th><th>Responsible for the implementation of cantonal policy and additional local policy</th><th>Responsible for the implementation of cantonal policy</th></tr></thead><tbody><tr><th>Municipal level</th><td>- Local housing policy: local regulations, local subsidy programmes, promotion and protection of affordable housing (e.g. non-profit housing, quotas for non profit housing, special land use plans, utilisation planning)</td><td>- Local energy policy: local regulations, local subsidy programmes, construction permits</td><td>- Municipal utilisation plan<br/>- Local subsidy programmes<sup>172</sup></td><td>- Municipal utilisation plan<br/>- Municipal zoning- and building regulation (BZO)<br/>- Re-zoning and compensation<br/>- Adaption of infrastructure</td></tr></tbody></table>

# 4 Housing retrofitting

## 4.1 The policy cycle: emergence of the issue and policy decisions

The public promotion of housing retrofitting in Switzerland has a long history dating back to the 1973 oil crisis to which the Swiss Federal Council and the parliament responded by comprehensively reorganising the country's energy policy. For the first time the issue was raised that houses should be better insulated and not excessively heated. The oil crisis, compounded by the first public discussions triggered by the publication of 'Limits to Growth' by the Club of Rome (Meadows et al., 1972), led to a gradual rethinking on the way energy was used. It further enhanced awareness on the dependence on imported energy sources (Gisler, 2022).

Perhaps the most important measure taken by the Federal Council in 1974 was to set up the 'Federal Commission for an Overall Energy Concept'. This commission was tasked with identifying the direction of Switzerland's energy policy and investigating whether it might be necessary to extend federal competences in this domain. The report presented by the commission in 1978 formulated three goals for a future energy policy: an adequate and secure energy supply, the guarantee of economically optimal energy prices, and the protection of people and their environment. It further recommended that the federal government should incorporate an energy article into the Constitution with the aim of creating the foundations for a more active federal energy policy. After prolonged debates, Article 89 (Energy Article/Energieartikel) was finally added to the Swiss Constitution in 1990. It stipulates that, within the framework of their responsibilities, the federal government and the cantons must

<footnote n="172">172 Municipalities have the discretion to implement support for NBS measures. However, such programs remain voluntary at the municipal level.</footnote>
establish the necessary prerequisites for securing an adequate, comprehensive, safe, economic, and ecological energy supply, and ensure an efficient and parsimonious energy use. The article also states that measures related to the energy use of buildings are mainly the responsibility of the cantons, even though the national government is strongly involved in the promotion of energy refurbishments. The next sub-section will therefore trace the development of energy efficiency policies at the federal level, and in the subsequent sub-section, we focus on the Buildings Programme (Gebäudeprogramm), i.e. on the most important instrument through which Switzerland is promoting energy refurbishments of its housing stock.

Switzerland's energy efficiency policies

Following the addition of the Energy Article to the Swiss Constitution in 1990, the Federal Council launched Switzerland's first energy policy in 1991. The programme "Energy 2000" (Energie 2000) aimed to promote a rational use of energy and renewable energies through voluntary measures. This programme was followed by the SwissEnergy (EnergieSchweiz) programme in 2001, which specifically focuses on energy efficiency of buildings. Up to date SwissEnergy remains Switzerland's central platform for information on energy efficiency, renewable energies and refurbishment (BFE, 2024b).

After the Energy Article passed, the Federal Assembly also began working on the Energy Act (Energiegesetz). Related debates were heated and continued for years, with the result that the Energy Act only came into force in 1999 (Zünd, 2019). The Act is legally binding and requires cantons to regulate energy use and renewable energy sources, for both new and existing buildings (Bundesversammlung, 1998).

Switzerland's energy policy does not only reflect awareness of energy being a scarce resource but also its commitment towards the Climate Change Convention which was approved at the 1992 Earth Summit in Rio de Janeiro and came into force on 21 March 1994 (United Nations, 1992). However, it soon became clear that the provisions of the Convention were insufficient and as a response, the Kyoto Protocol was passed in 1997. In the Protocol, the participating industrialised countries committed to reduce their greenhouse gas emissions between 2008 and 2012 by an average of 5.2% in comparison to 1990. Switzerland made the same formal commitment as the European Union to reduce greenhouse gas emissions by an average of 8% between 2008 and 2012 (BAFU, 2023c).

In response to its commitments made to the Kyoto Protocol, the Swiss government passed the CO2 Act (CO2-Gesetz), which came into effect in 2000 and is legally binding. The law mandates a 10% reduction in CO2 emissions by 2010, relative to the 1990 levels (BAFU, 2000). It also includes a provision for a CO2 levy on fossil fuels used for heating, lighting, or electricity generation (excluding gasoline and diesel), to be introduced after 2004, should other reduction measures fail to meet the targets. The CO2 levy was ultimately introduced in 2008 and has been increased several times due to the shortfall in achieving the reduction goals (BAFU, 2020).

In 2010, the launch of the Buildings Programme (Gebäudeprogramm) marked a significant step in Switzerland's energy and climate policies by offering financial incentives for energy-efficient renovations. This federal-cantonal partnership, partially financed through the CO2
levy, aims to reduce heating energy consumption and to improve insulation standards across
the country (BFE, 2023)<fnref n="173" />.

Following the nuclear catastrophe of Fukushima, the Federal Council introduced the Energy Strategy 2050 (Energiestrategie 2050), a long-term vision focused on phasing out nuclear power and increasing renewable sources, such as solar and wind energy. Retrofitting buildings became a key component of the strategy to curb energy consumption and emissions within the housing sector. As part of the new Energy Strategy 2050, the Energy Perspectives 2050 were developed as political guidelines and the revision of the Energy Act (see below) was advanced (BFE, 2013, 2018).

On the international front, the 2015 Paris climate conference led to an agreement for the post-2020 era that committed all states to reducing their greenhouse gas emissions and largely eliminated the previous distinction between industrialised and developing countries. Switzerland ratified the Paris Agreement in October 2017, thereby committing to halve its emissions to 1990 levels by 2030, partially through international emissions reductions.

In 2016, the 1999 Energy Act dating was revised. The updated law, which came into force in 2018, sets clear targets for expanding electricity generation from renewable sources. It also includes an interim target of reducing per capita energy consumption by 43% by 2035. (Federal Assembly, 2018). With this revision, the Federal Assembly also decided to extend the Buildings Programme (Eidgenössisches Departement für Umwelt, Verkehr, Energie und Kommunikation UVEK, n.d.).

In 2021, Switzerland enacted its "Long-Term Climate Strategy 2050" (Langfristige Klimastrategie 2050), a comprehensive and binding roadmap to achieve net-zero greenhouse gas emissions by 2050 (FOEN, 2023). A major focus of this strategy is the buildings sector, aiming at reducing greenhouse gas emissions from the existing building stock to zero by 2050. This will require a swift change in energy refurbishment practices, as many existing oil and gas heating systems continue to be replaced with new fossil-based systems, undermining the long-term goals of the Climate Strategy (Federal Council, 2021).

The Energy Perspectives 2050+ (Energieperspektiven 2050+), adopted in 2021, outlines Switzerland's long-term energy policy and serves as basis for decision making. The report presents two main scenarios: ZERO and BAU (business as usual), with the ZERO scenario further divided into several subvariants. All ZERO scenarios aim to achieve net-zero greenhouse gas emissions by 2050, in line with Switzerland's climate goals, while ensuring a secure and stable energy supply. The overarching strategy calls for a reduction in energy consumption across all sectors, along with the replacement of carbon-intensive energy sources with renewable alternatives. The strategy highlights significant reductions in energy consumption for space heating despite an increase in the energy reference area for housing. The goal is that 95% of Switzerland's households will be heated with heat pumps or district heating by 2050 (BFE, 2021).

A proposed revision of the CO2 Act sought to establish more ambitious climate targets,
including stricter regulations for buildings. This included additional taxes on fossil fuel heating

<footnote n="173">¹⁷³ Further details on the Buildings Programme are provided in Section 0.</footnote>
systems, the creation of a climate fund, and further incentives for renewable energy retrofitting. However, the revision was rejected in a popular vote in June 2021, largely due to concerns about increased costs for households and businesses. This vote marked a setback for Switzerland's climate policy, in particular in the relation to the effort to accelerate retrofitting in the building sector (BAFU, 2021).

In 2019, a popular initiative "For a healthy climate (Glacier Initiative)" (Für ein gesundes Klima - Gletscher-Initiative) called for a ban on the use of fossil fuel by 2050. In response, the Federal Assembly and the Federal Council developed an indirect counterproposal, the "Climate and Innovation Act" (Klima- und Innovationsgesetz) which was passed in 2023 and came into force in January 2025. This Act legally enshrines Switzerland's commitment to reaching net-zero greenhouse gas emissions by 2050. In the buildings sector, it sets a target for an 82% reduction of emissions by 2040, with a complete decarbonization by 2050. The Act also introduces a Stimulus Programme (Impulsprogramm) that complements the Buildings Programme with additional subsidies. The specific measures and subsidies to support this transition are outlined in the Climate Protection Ordinance (Klimaschutzverordnung) and in the Energy Ordinance (Energieverordnung) which are both legally binding (BFE, 2023; Bundesversammlung, 2022).

The Swiss Engineers and Architects Association (SIA) set a new building standard called Climate Path (Klimapfad, SIA 390/1) in 2025 to limit CO2 emissions in the building sector. As a holistic consideration of construction, operation and induced mobility over the entire life cycle of buildings, it allows to evaluate and compare new developments and retrofits. The SIA's standards are highly influential in the construction industry, and the association plays an important role in political decision-making (Ménard, 2025).

In addition to national policies and initiatives, certifications with national and international labels have a growing impact on energy efficient refurbishments. Especially for international investors, green labels are important cachets to persist with a portfolio in an EU wide market. In Switzerland, the most important certification for sustainability is the Sustainable Building Standard Switzerland SNBS (Standard Nachhaltiges Bauen Schweiz) which was originally developed for new buildings but is increasingly applied also to refurbishments. The SNBS covers social, economic, and ecological sustainability. Labels are voluntary instruments that can also be applied only partially. They entail benefits like increased density (Representative of Lemon Consult AG, personal communication, May 7, 2025).
<figure><img src="image_91.png" /><figcaption>Figure CH27. Timeline of policies, initiatives and strategies regarding energy refurbishments in Switzerland</figcaption></figure>

The Buildings Programme

In Switzerland, buildings are responsible for over 40% of energy consumption and around a third of the CO2 emissions. It is estimated that currently more than one million houses have little or no insulation and are therefore in urgent need of energy-efficient refurbishment. In addition, more than 60% of all residential buildings are still heated with fossil fuels or conventional electricity (Bundesamt für Statistik, 2024a). According to official estimates, in a significant portion of buildings better insulation can reduce heating requirements by more than half. Furthermore, by switching from fossil-fuelled heating to renewable energies, CO2 emissions during operation can be reduced to almost zero (EnDK & Bundesamt für Energie BFE, 2024).

The Buildings Programme was launched in 2010 with the aim to reduce the energy consumption of the building stock and to cut CO2 emissions. It provides financial subsidies to the owners of any type of building for energy refurbishments (e.g. replacement of windows, replacement of the heating system, and insulation of walls and roofs). The current Buildings Programme builds upon a previous building programme that was implemented until 2009 with public support by the Stiftung Klimarappen (Interface Politikstudien Forschung Beratung & Ernst Basler + Partner AG, 2010). With the revision of the Energy Act 2018, the Federal Assembly decided to continue the Buildings Programme (Eidgenössisches Departement für Umwelt, Verkehr, Energie und Kommunikation UVEK, n.d.).

The federal subsidies provided through the Buildings Programme only apply if the respective canton also has a financing program for energy refurbishments. Details of the subsidy schemes' implementation are explained in section 3.2. As previously mentioned, the Buildings
Programme is complemented by the Stimulus Programme that was introduced under the Climate and Innovation Act. This temporary subsidy programme is designed to address areas where existing subsidies are insufficient and will run for ten years. It primarily aims at fostering the replacement of fossil fuel heating in multi-family buildings and electric heating systems with renewable alternatives. In total, a credit of 2 billion CHF were allocated to the Stimulus Programme (Das Gebäudeprogramm, 2024b).

4.2 The implementation process

As mentioned in the previous sections, housing retrofitting in Switzerland is primarily taking place with the support of the Buildings Programme, which is a joint initiative of the confederation and the cantons. Funding is provided through a partial earmarking of the CO2 levy at the federal level, as well as contributions from the cantons. Since 2010, one third of the revenue from the CO2 levy has been invested in measures to reduce CO2 emissions from buildings. This funding is capped at CHF 450 million per year and is distributed to the cantons as an overall federal contribution. To receive this contribution, a canton must have a programme in place that promotes energy-efficient building renovations, including improvements to building envelopes and building technology, as well as the replacement of electric and oil heating systems.

The federal contribution is divided into two components: a basic contribution per inhabitant and a supplementary contribution. The basic contribution can account for up to 30% of the available funds. The supplementary contribution is limited to twice the amount the canton has approved for its own programme. The funds provided by both the Confederation and the cantons support a variety of energy-related measures, including the insulation of roofs and façades, the utilisation of waste heat and the use of renewable energies (BFE, 2024c). According to a representative of the BFE, the buildings programme primarily aims to promote energy efficiency and, secondarily, decarbonisation, as related measures create greater deadweight effects (Representative of SFOE, personal communication, May 8, 2025).

While cantons are free to determine which measures to support and under what conditions, the Conference of the Cantonal Energy Directors (Konferenz der Kantonalen Energiedirektoren, EnDK) has developed the “Harmonised Promotion Model of the Cantons” (Harmonisiertes Fördermodell der Kantone, HFM), which offers a standardized framework for developing cantonal subsidy schemes. Nevertheless, each canton is entitled to customise its programme based on regional needs and available financial resources. The first version of the HFM of 2003 was revised in 2007, 2009 and again in 2015 to reflect new policies, developments and evaluations of the Buildings Programme (BFE & EnFK, 2016). In some cantons, regulatory tools have been introduced, like the forbidding of the replacement of obsolete heating systems with fossil fuel heating systems (Zurich, Basel Stadt, Geneva, Neuenburg).

Additionally, the cantons have jointly developed the “Cantons’ Model Regulations in the Energy Sector” (Mustervorschriften der Kantone im Energiebereich, MuKEn) which set guidelines for energy use for both new and existing buildings. These regulations have been periodically updated since 1992, with the most recent version dating from 2014. Also the MuKEn can be adapted by the cantons to their specific needs and incorporated accordingly into their canton-
specific legislation (Konferenz Kantonaler Energiedirektoren, 2018). However, according to EnDK, the requirements of most of the 26 cantonal energy laws are practically identical, which explains why the Swiss building stock is relatively homogeneous in terms of energy efficiency. (Representative of EnDK, personal communication, May 8, 2025).

An evaluation of the Buildings Programme for the phase from 2010 to 2014 revealed that its impact was below expectations, suggesting that meeting targets in the buildings sector will be challenging. Data collected by the BFE suggests that funds are actively used by larger, more affluent real estate owners (Representative of SFOE, personal communication, May 8, 2025). Some cantons reduced their budgets, which affected the federal contributions, while in others, demand for subsidies was lower than anticipated (Bundesrat, 2016). However, since 2016, the federal funding for the Buildings Programme has increased significantly, from slightly over CHF 150 million to CHF 425 million in 2022, hinting at a growing momentum for energy refurbishments. Indeed, energy renewal rates between 2011 and 2020 were around 40% to 50% higher than in the previous decade (BFE, 2024a). However, even though representatives of several administrative levels emphasize the importance of the Buildings Programme to attain climate goals, a drastic reduction of its funding is currently under discussion (Representative of EnDK, personal communication, May 8, 2025), (Representative of SFOE, personal communication, May 8, 2025).

<figure><img src="image_92.png" /><figcaption>Figure CH28. Federal payments for the Buildings Programme by measure type, in CHF. Source: MURE Database (2023).</figcaption></figure>

4.3 Size and role of the market

The energy refurbishments benefit from significant public support; over 3.6 billion francs in subsidies have been disbursed under the Buildings Programme between 2010 and 2023 (Das
Gebäudeprogramm, 2024a). Subsidy payments in 2023 alone totalled CHF 528 million. Private market actors (specialized consultants and the building industry) play a key role in the implementation of energy refurbishments. The building sector also supports SwissEnergy financially and has a strong lobby for maintaining the Buildings Programme (Representative of SFOE, personal communication, May 8, 2025). Indeed, according to a recent official publication, so far the Building Programme had an employment effect of 3025 man-years (EnDK & Bundesamt für Energie BFE, 2024). Accordingly, it may be said that the Buildings Programme has been quite successful in the creation of green jobs, in line with the objectives of the European Green Deal.

However, apart from incentives and funding, there are also market-related factors that affect real estate owners' decision-making about energy retrofitting. For example, the currently unpredictable energy prices strongly building owners' attitudes towards refurbishments. Fluctuating energy pricing undermine a reliable planning of renewable energy systems, leading to a slowdown of retrofitting (Representative of EnDK, personal communication, May 8, 2025).

As subsidies only cover a fraction of the refurbishment costs, homeowners typically rely on private financing mechanisms such as mortgages or construction loans for retrofitting projects. Banks set a credit limit based on available equity, generally applying an 80/20 equity-to-loan ratio (hausinfo, 2024). Financing depends on the potential to increase the value of a property or to achieve energy savings. The public sector plays a crucial role through subsidies in supporting retrofitting projects that align with sustainability goals, but that are not immediately economically viable because, for example, the initial investment is high, or not all external costs are calculated correctly. Ideally, these public funds enhance market-based financing, incentivizing homeowners to pursue energy-efficient renovations (BFE, 2024b).

4.4 The multilevel governance process

Switzerland's direct democracy and federal system plays an important role in the climate debate, as shown once again when the revision of the CO2 Act was rejected by the majority of the voters in 2021. The governance of housing retrofitting policies is based on a multilevel system. The cantons are primarily responsible for reducing the energy consumption in buildings and hence for the implementation of the Buildings Programme and are also in charge of processing and approving the funding applications.

As mentioned earlier and illustrated in Figure 3, the funds for the Buildings Programme come from federal as well as cantonal sources: a share of the CO2 levy (federal contribution) and cantonal contributions. Cantonal contributions range from CHF 130 to 200 million annually, while federal contributions from the CO2 levy total up to CHF 450 million annually, with an average of CHF 400 million (BFE, 2023). The federal support consists of a basic contribution and a supplementary contribution which can be twice as high as the funds approved by the respective canton. This structure incentivizes cantons to allocate higher budgets, as larger cantonal contributions result in higher federal funding. Additional cantonal funding programs beyond the Buildings Programme are also possible (BFE, 2024c).

As argued by an energy expert, there is a fundamental social equity problem with the programme as it provides public funding in the form of subsidies to private landlords that enhance the value of their property, which in turn enable them to increase rents. However,
social problems that such refurbishments may cause, such as evictions and unaffordable rents for the most vulnerable people have to be absorbed by the state (Representative of SFOE, personal communication, May 8, 2025). Furthermore, the Buildings Programme does not include any social criteria in defining subsidy entitlements, thus externalising its eventual negative social impacts.

Additional subsidy programmes, complementing the federal and cantonal programmes, can also be put in place at the municipal level. Predominantly larger municipalities and cities have launched their own subsidy programmes for energy refurbishments. For example, the city of Zurich provides additional subsidies for the replacement of heating systems, photovoltaic systems, and building renovations (Stadt Zürich, 2024a). But also smaller municipalities such as for example Amriswil in the canton of Thurgau with a population of 14,300 in 2023 (Kanton Thurgau, 2024) have their own local funding for EEP programmes. In addition to building renovations, they support for example battery storage, charging infrastructure, cargo bikes, bike trailers, and greening of roofs and facades (Stadt Amriswil, 2024). The online platform Energy Franc (Energiefranken), supported by the Electricity Provider of the Canton of Zurich (Elektrizitätswerke des Kantons Zürich, EKZ), provides a comprehensive overview of subsidy schemes at different levels of government.

Besides federal, cantonal, and municipal offices for energy, other important actors in the energy refurbishment sector are the “Conference of the Cantonal Energy Directors” (EnDK – Konferenz der Kantonalen Energiedirektoren), which assembles the cantons in the energy and climate sector at government level, the specialist level Conference of Energy Agencies (EnFK – Energiefachstelle Konferenz), and the “Conference of Heads of Environmental Protection” (KVU – Konferenz der Umweltämter). These bodies jointly develop and coordinate the cantons’ energy and climate policy activities, such as for example the HFM and the MuKEn (EnDK & Bundesamt für Energie BFE, 2024). They are important because, as was mentioned, energy policy, building policy and the specifications for energy standards in the construction industry are cantonal competences.

In most cantons, strategies, concepts, guidelines or planning reports on the canton's energy and climate policy with concrete objectives and action plans – including rules on which measures are subsidised by the Buildings Programme – have been developed only in recent years, based on the MuKEn. Targets are defined based on the objectives of federal legislations in the energy and CO2 domain, among others. Despite extensive guidelines, a study commissioned by WWF Schweiz found that the implementation of energy and climate policies in the building sector varies significantly across cantons. While the canton of Basel-City has adopted exemplary policies (fulfilling 4 out of 5 points), 11 cantons only fulfil 2 out of 5 points, while none of the cantons is implemented a policy fully in line with the Paris Agreement (EBP Schweiz AG, 2019).
<figure><img src="image_93.png" /><figcaption>Figure CH29. Multilevel governance process of the Buildings Programme. Source: authors' own</figcaption></figure>

<table><thead><tr><td>Sector</td><td>Level of governance</td><td>Name</td><td>Role</td><td>Date of appearence</td></tr></thead><tbody><tr><td>Public</td><td>National</td><td>Federal Office of Energy (SFOE)</td><td>Implementation of federal energy policies</td><td>1907</td></tr><tr><td>Public</td><td>National</td><td>Federal Office for the Environment (FOEN)</td><td>Implementation of federal climate policies</td><td>1971</td></tr><tr><td>Public</td><td>Cantonal</td><td>Cantonal offices of energy</td><td>Implementing their canton's energy policies</td><td>late 1970s- early 1980s, depending on Canton</td></tr><tr><td>Public</td><td>National</td><td>Conference of Heads of Environmental Protection (KVU – Konferenz der Umweltämter).</td><td>Promotion of sustainable development, including energy efficiency initiatives. Coordination of environmental policies across cantons; fostering collaborations between cantons and other stakeholders.</td><td>1976</td></tr><tr><td>Public</td><td>National</td><td>Conference of the Cantonal Energy Directors (EnDK – Konferenz der Kantonalen Energiedirektoren), EnDK</td><td>Development of common guidelines for cantonal energy policies and frameworks for regulating energy use in existing and new-built buildings</td><td>1988</td></tr><tr><td>Public</td><td>National</td><td>Conference of Energy Agencies (EnFK –</td><td>Connect energy experts across the country, provide support to energy offices, ensure that local and</td><td>1997</td></tr></tbody></table>
<table><tr><td></td><td></td><td>Energiefachstelle Konferenz</td><td>regional energy initiatives align with national goals.</td><td></td></tr><tr><td>Public</td><td>Cantonal</td><td>EKZ (Energieversorgung Zürich/Energy supply Zurich)</td><td>Provides consulting services to optimise energy use, including energy refurbishments and offers financial incentives for renovations. Collaborates with other actors to foster large-scale energy refurbishments, including residential buildings. Overall responsibility for the Platform “Energie Franken”</td><td>1997</td></tr><tr><td>Private</td><td></td><td>Faktor Journalisten AG</td><td>Collaborations with energy companies, NGOs, government agencies, and other stakeholders in communication on energy transition, environmental protection, climate change, and sustainable development. Responsible for data collection on available subsidies by commune for Energie Franken</td><td>2001</td></tr><tr><td>NGO</td><td>National</td><td>Stiftung Klimarappen</td><td>Was responsible for the implementation of the energy refurbishment programme that preceded the Buildings Programme</td><td>2008</td></tr><tr><td>Public</td><td>National</td><td>Energiehub Gebäude</td><td>Platform for building owners, planners, and energy consultants to access information and resources about energy efficiency measures for buildings. It helps stakeholders identify, plan, and implement strategies that reduce energy consumption in buildings, optimize heating, cooling, and lighting systems, and ensure better insulation and overall energy performance.</td><td>2014</td></tr><tr><td>Public</td><td>Municipal</td><td>Municipal offices of energy</td><td>Implementing local energy policies</td><td>Depending on municipality</td></tr><tr><td>Private</td><td>National/local</td><td>Consulting firms and networks of certified consultants on energy efficiency (e.g.</td><td>Advisory services to improve energy efficiency in homes and businesses. Support for energy-efficient renovations,</td><td></td></tr></table>
<table><caption>Table CH2. Actors involved in the policy cycle of energy retrofitting</caption><tr><td></td><td></td><td>SuisseEnergie, Energieberater Schweiz, Enco AG, Green Tech AG, Minergie, Swiss Energy and Environmental Engineering (ESE)</td><td>including insulation, heating systems, and renewable energy solutions</td></tr><tr><td>Private</td><td>National/local</td><td>Building industry, building technology companies (e.g. Losinger Marazzi, HRS Real Estate AG, Baumer Group, Züblin Schweiz AG, Walo Bertschinger AG</td><td>Implementation of energy refurbishments, including thermal insulation, windows, and renewable energy installation</td></tr></table>

## 4.5 Assessments, achievements, and challenges

As mentioned in Section 3.2, the volume of federal contributions to the Buildings Programme is the main aspect that is being monitored and regularly published, for example in its Annual Reports. However, it may be argued that the real impact of the programme should rather be assessed in terms of the reduction in energy consumption and CO2 emissions. Since its inception in 2010, the programme has resulted in a decrease of 3.8 billion kilowatt-hours (kWh) in energy consumption and a reduction of 1,064,000 tons in CO2 emissions (Das Gebäudeprogramm, 2024a). In its latest evaluation, the Buildings Programme was deemed effective, as the savings per Swiss Franc exceeded initial expectations (Bundesrat, 2016).

Nevertheless, several concerns and critiques have been raised regarding the programme, its funding structure, along with equity considerations. Concerns have also been raised with regard to its potential **deadweight effect** as property owners receive subsidies even if they would have undertaken energy refurbishment also without them. An evaluation from 2023 estimated that the deadweight effect accounts for approximately 47% (BFE & EFK, 2024). These numbers, however, were only based on cantonal and national experts' estimates (Representative of SFOE, personal communication, May 8, 2025) (Representative of EnDK, personal communication, May 8, 2025). Furthermore, an evaluation commissioned by the Stiftung Klimarappen confirms that households with higher gross incomes have disproportionately benefitted from the programme (Interface Politikstudien Forschung Beratung & Ernst Basler + Partner AG, 2010), suggesting that it could exacerbate social inequality. As an energy expert stated, there is a basic social problem with the funding: although it benefits from public funding, the subsidies are provided to private landlords. However, inequalities such as energy poverty and social problems caused by increasing housing affordability problems are absorbed by the state (Representative of SFOE, personal communication, May 8, 2025).

There is increasing concerns that energy refurbishments are substantively contributing to the loss of affordable housing with severe consequences on lower income people (e.g. Suppa et
al., 2019). In Switzerland, costs related to property improvements—such as energy refurbishments—can be passed on to tenants in the form of rent increases, provided these improvements increase the property's value (Burkhalter, 2014). Under current regulations, which date back to 1977, 50–70% of the investment in extensive renovations can be considered "value-enhancing" and subject to rent increases, minus the subsidies received. This rule was originally intended to incentivize landlords to renovate (King et al., 2019). However, the relatively weak tenant protections (Debrunner, Kolocek, et al., 2024) make **renovictions**—forced evictions due to renovations—a more appealing option for landlords. This enables them to carry out extensive renovations and subsequently charge significantly higher rents. A case study covering ten instances revealed that, even when accounting for lower utility costs, tenants experience an increase in financial burden following energy refurbishments, particularly when rental contracts are terminated (B,S,S & Basler & Hofmann AG, 2014).

To date, subsidies for retrofitting have been offered based exclusively on technical criteria, without any social equity consideration (Debrunner & Hartmann, 2020). The impacts of these policies are multifaceted, especially concerning housing quality and affordability, affecting in particular lower-income tenants in urban areas and agglomerations. **Renovictions** became a widely diffused practice in the 2010s and have remained high, particularly in urban centres (Vogel, 2019). In Zurich, for example, 30% of all housing renovations between 2021 and 2022 entailed renovictions, affecting over 1,000 individuals annually (Stadt Zürich, 2024d). Research with focus on the canton of Zurich indicates that renovations and replacement constructions contribute to the displacement of lower-income and vulnerable tenants, with new tenants in renovated or rebuilt buildings earning, on average, 3,000 Swiss Francs more than those they replace (Kaufmann et al., 2023). Nationwide data on renovictions remains difficult to obtain (Vogel, 2019)

While energy refurbishments themselves do not necessarily entail comprehensive renovations (BWO, 2016), the subsidies granted under the Buildings Programme make such renovations financially more attractive. This, in turn, increases the likelihood of renovictions and rent increases, potentially accelerating gentrification in certain areas.

In recent years, the federal government has explored ways to modify the subsidy structure to better align with housing policy objectives. A study commissioned by the Federal Office of Housing (BWO, 2016) outlines various options and their anticipated effects on energy policy, housing affordability, government spending, and enforcement (BWO, 2016). One recommendation is to link subsidies to additional criteria, such as vacancy rates, in order to prevent the deadweight effect in high-demand areas where renovations (and energy refurbishments) would be profitable even without subsidies. Another proposal is to make the obtainment of subsidies contingent on landlords' agreement not to evict tenants or to comply with rent control regulations. A stronger alignment of energy and housing policies could also entail amendments to tenancy laws, such as reducing the percentage of renovation costs that can be passed on to tenants through rent increases or enhance eviction protections.

While such measures could mitigate the risk of renovictions and excessive rent increases, they have been criticized for potentially reducing incentives to renovate, undermining Switzerland's energy policy goals. Furthermore, they are often seen as an infringement on property rights
(BWO, 2016), or are regarded as costly and difficult to enforce. Up to date, none of these measures have been adopted at national level. However, some cantons, for example Geneva and Basel Stadt, have introduced stricter rent controls and tenant protections to address the risks of renovations, gentrification, and rising rents. For instance, under Basel's new housing protection laws, landlords must seek approval from a committee before raising rents following a renovation. These measures aim at reducing gentrification and renovation risks, but have also been criticised for slowing down renovations, which harms smaller enterprises in the building sector (Hauser, 2023), (Künzle & Kenan, 2024).

Nevertheless, retrofitting also has the potential to reduce housing inequality. If rent increases resulting from energy refurbishments are controlled and do not outweigh the savings on utility costs, retrofitting could alleviate **energy poverty**, particularly for low-income households. Over time, the financial relief from reduced energy consumption could directly ease the burden on families in need.

<table><thead><tr><td>Policy / Programme</td><td>Measured impacts on housing inequalities</td><td>Potential impacts on housing inequalities</td></tr></thead><tbody><tr><td>Buildings Programme</td><td>-</td><td><strong>Inefficient Funding:</strong> In 2023, 47% of recipients report they would have retrofitted without subsidies.<br/><br/><strong>Unequal Benefits:</strong> Only property owners and the building industry directly benefit from the Buildings Programme.<br/><br/>Eligibility for subsidies exclusively based on technical criteria; socioeconomic factors are not considered<br/><br/><strong>Negative Social Impacts:</strong> Energy retrofits often trigger full renovations, leading to evictions, higher rents, displacement and gentrification</td></tr><tr><td>Stimulus Programme</td><td>-</td><td><strong>Inefficient Funding:</strong> The Stimulus Programme focuses on measures, which would often be retrofitted without funding (e.g. decarbonisation of heating systems)</td></tr><tr><td>Swiss tenancy law: landlords can transfer 50-70% of renovation costs to tenants</td><td>Rent increases typically exceed energy cost savings (BWO, 2016)<br/><br/>Cost transfers are often not controlled (only if tenants insist)</td><td><strong>Incentivized Rent Hikes:</strong> Tenancy law encourages combining energy retrofits with value-adding renovations, allowing greater rent increases.</td></tr></tbody></table>
<table><caption>Table CH3. Summary table of measured and potential impacts of retrofitting policies on housing inequalities.</caption>
   <tr>
    <td>
    </td>
    <td>
     Reduced Affordability: Retrofitted homes often become unaffordable for low-income tenants.
    </td>
   </tr>
  </table>

5 Nature-Based Solutions

5.1 The policy cycle: emergence of the issue and policy decisions

Currently, Switzerland lacks policies explicitly promoting nature-based solutions (NBS), as this concept is not yet used at national level. However, NBS are closely related and in some cases reflected into policies on biodiversity, climate change adaptation, and river restoration. Public awareness on climate change and environmental protection are playing an important role in advancing NBS in Switzerland. As a result, the number of policies instruments aiming at promoting NBS have grown rapidly over the past decade, a sharp contrast to the slower developments before 2010. The Swiss Spatial Planning Act only contained a planning principle stating that residential areas should include 'a lot of green and trees', which, although vague, was still legally useful wording. Furthermore, the Swiss Nature and Heritage Conservation Act (Natur- und Heimatschutzgesetz, NHG) assigned all cantons with "ecological compensation"<fnref n="174" /> in intensively utilised areas in 1988 (SR 451 - Art.18 B2, 1966). However, already in 1996, WWF Switzerland (*WWF Schweiz*) criticized spatial planning practices that led to excessive land sealing without adequate compensation in the form of land or river restoration (Bernath et al., 2024). This triggered public debates on the need of actions that today we would refer to as NBS. The first popular initiative that promoted NBS (without using this term) was launched by the Swiss Fishing Federation (*Schweizerischer Fischerei-Verband, SFV*) in 2005. Named "Living Water (River Restoration Initiative)" (*Lebendiges Wasser (Renaturierungs-Initiative)*) it primarily aimed to address the extinction or near-extinction of native fish species by calling for an amendment to the Swiss constitution. It advocated for river restorations and the establishment of cantonal funds to protect biodiversity and improve aquatic habitats. The initiative prompted the Swiss Parliament to draft an indirect counterproposal in 2010, which addressed many of the initiative's goals, but gave more weight to the interests of the water energy industry. It proposed alternative financing mechanisms for river restoration and to incorporate these issues into amendments to the Water Protection Act (*Gewässerschutzgesetz*) rather than to the constitution. The initiative was eventually withdrawn, and in 2011, while the Water Protection Act amendments were enacted.

Nevertheless, these amendments have faced opposition, particularly from the right-wing party SVP, the Swiss Farmers' Union, the electricity industry, and power plant operators, which objected to cantons' requirement to designate watercourse areas that cannot be used for

<footnote n="174">¹⁷⁴ Collective term for measures that serve to preserve and promote habitats and their connectivity in intensively utilised or densely populated landscapes. According to the FOEN, ecological compensation measures mainly promote native biodiversity in resident areas.</footnote>
intensive agriculture or construction. At the same time, the slow pace of river restorations has also drawn criticism in relation to the increasing number of floods and landslides caused by climate change. As a result, river restorations are increasingly advocated as a key NBS for the management of climate change-induced floods (Bernath et al., 2024).

At national level, the Federal Council began developing a Climate Change Adaptation Strategy (Strategie Anpassung an den Klimawandel) in relation to the 2011 revision of the CO2 Act (CO2-Gesetz), which requires the Federal Council to coordinate climate adaptation measures. In 2012, the Federal Council released the first part of this strategy, titled "Objectives, Challenges, and Fields of Action" (Schweizerische Eidgenossenschaft, 2012). While not explicitly mentioning NBS, it identified heatwaves and floods as growing natural hazards due to climate change and proposed mitigation strategies that align with NBS principles. Key measures included creating and enhancing green infrastructure, promoting open spaces, preventing soil sealing, and using green and shaded areas to mitigate heatwave impacts. River restoration was also highlighted as a measure for flood protection.

In 2014, the Federal Council published the Action Plan for the Period 2014-2019 as part of the Climate Change Adaptation Strategy (Schweizerische Eidgenossenschaft, 2014). This plan, while again not directly referring to NBS, emphasized the importance of spatial planning in adapting urban areas to increasing heat stress. It called on cantons and municipalities to take responsibility for urban climate adaptation, with the federal government providing guidelines and support, but it is not legally binding. A notable example is the guide "Heat in Cities: Principles for Climate-Adapted Urban Development" (BAFU, 2018), which offers best practices for urban planning.

Building upon the previous one, the Federal council published a second Action Plan in 2020 (Schweizerische Eidgenossenschaft, 2020). One of its main foci is the enhancement of urban green spaces and watercourse areas. It further aims to raise awareness about the ecosystem services provided by green and blue infrastructure. Municipalities, supported by cantons and federal offices, are encouraged to adopt these measures. As of 2020, the federal government funded 81 pilot projects addressing climate change adaptation and mitigation at municipal and regional levels.

While climate change adaptation is the main concern of the projects promoted by the Action Plans, initiatives that may be labelled as NBS are also being promoted with the aim of protecting biodiversity.

For example, already back in 2009, the Federal Council mandated the Federal Office for the Environment (FOEN) to develop a strategy on biodiversity, which was presented to Parliament in 2011. The strategy primarily entailed securing ecological infrastructure and providing and enhancing ecological spaces in urban areas. It gained support from the Social Democratic Party (SP) and the Christian Democratic People's Party (CVP), but was criticised for its lack of concrete action, particularly from the Green Party (Grüne Schweiz), the Liberals (FDP), and the Swiss People's Party (SVP), who feared excessive regulation and costs (Flückiger, Porcellana, Gerber, et al., 2024). Nevertheless, it was adopted in 2012, and a participatory process was launched to develop an Biodiversity Action Plan, which was finally adopted in 2017 for the period 2017-2023 (Bundesrat, 2017). Although the Action Plan does not use the
term NBS, it aimed to create a nationwide ecological infrastructure, integrating settlements into ecological networks. This infrastructure was expected to have additional benefits such as improving air quality, regulating microclimates, and reducing noise.

Despite criticism regarding delays, the lack of funding, and the non-binding nature of the plan, the Action Plan was extended into 2024 and the development of a second Action Plan (2025-2030) underway. However, in September 2024, three environmental organizations—Pro Natura, WWF, and BirdLife Schweiz—issued a joint statement criticizing the draft of the Action Plan for its insufficient funding and effectiveness (Pro Natura et al., 2024).

The second Action Plan, published in November 2024, reiterates the importance of promoting biodiversity in urban areas through the creation and enhancement of green spaces, integration into ecological networks, and land and river restoration. For the first time, the plan explicitly uses the term NBS (naturbasierte Lösungen) for one of the 15 measures under the FOEN's responsibility mentioned in the Action Plan (Bundesrat, 2024). This measure outlines plans for the Confederation to oversee NBS projects and support at least 30 regional and municipal NBS projects by 2030. Municipalities remain key players in the implementation of NBS. Following a recent revision of the CO2 Act, which came into force in January 2025, the federal government has launched the adapt+ funding programme to promote measures to adapt to climate change, including NBS. Starting in August 2025, the program is planned to run until 2030 with an annual budget depending on submitted projects, mainly by cantons, regions, municipalities and organisations. This year, around 1.5 million has been allocated for the funding programme (BAFU, 2025).

Stronger commitments towards the biodiversity conservation were also sought by the popular initiative titled "For the Future of Our Nature and Landscape" (Biodiversity Initiative) (Für die Zukunft unserer Natur und Landschaft (Biodiversitätsinitiative)) of 2019, which was launched by environmental organizations, including, among others, the Swiss Fishing Federation. The initiative demanded increased funding for biodiversity, more protected areas, and greater responsibility for cantons in preserving landscapes. Critics argued that the initiative would negatively impact agriculture, energy production, and tourism and incur significant costs for both the Confederation and the cantons (Flückiger, Porcellana, & Ziehli, 2024). With these arguments they succeeded persuading 63% of the voters who rejected the initiative by popular vote in September 2024.
<figure><img src="image_94.png" /><figcaption>Figure CH4. Timeline of policies, initiatives and strategies affecting NBS goals in Switzerland</figcaption></figure>

5.2 The implementation process

The implementation of NBS policies at cantonal or municipal level is not explicitly regulated or
defined at the national level. While national strategies on biodiversity and climate change
adaptation recognize cantons and municipalities as key partners in implementing related
measures, they do not provide clear guidance on how this implementation should unfold at
lower levels of governance. As a result, so far none of Switzerland's 26 cantons developed a
strategy specifically focused on NBS. Since 2008, the Federal Office for the Environment
(FOEN) started supporting the cantons with project-specific financial contributions for a period
of up to 4 years through environmental sector programme agreements (Programm-
vereinbarungen im Umweltbereich) (BAFU, 2008). However, it is the responsibility of the
cantons to include measures for landscape politics and ecological compensation in their
legislation. By early 2022, only 17 out of the 26 cantons adopted strategies for climate change
adaptation, while in the remaining cantons, such strategies were still under preparation (BAFU,
2023a). Notably, the Climate Strategy of the Canton of Thurgau, published in December 2022,
is the only one to explicitly mention NBS (naturbasierte Ansätze). This is likely related to the
term's recent emergence, as NBS were introduced into national policies only in 2022
(Bundesrat, 2022). Cantons pursue different strategies. For example, Basel Stadt uses an
added-value levy (Mehrwertabgabe), which has to be paid when a building permit is issued, to
fund public green spaces. Even though the majority of the cantons are still without an
operational strategy, it is argued that the need for climate adaptation is widely recognized at
the cantonal level (BAFU, 2023a).

At the municipal level, there has been a notable increase in climate strategies and action plans
since 2020. While early efforts focused on energy related issues, the first comprehensive
climate strategies began to appear in 2015. Since then, there has been a significant increase in the number of cities and towns developing climate-related policies (Schweizerischer Städteverband et al., 2024). However, currently, 97% of Swiss municipalities are addressing climate change to some extent, but only 31% adopted specific strategies or measures for climate adaptation. A recent study on the integration of climate change adaptation goals in Swiss municipalities concluded that local adaptation measures remain rare, largely depending on individual stakeholders' initiatives or the occurrence of extreme events (Braunschweiger & Pütz, 2021). Local governments have expressed frustration over the lack of clear directives on climate change adaptation at the cantonal and municipal levels, questioning whether direct national legislation would be politically feasible. Many municipalities have called for more guidance and stricter legal requirements from higher levels of government, particularly from cantons (Schweizerischer Städteverband et al., 2024). In response to this lack of support, the FOEN has issued model clauses for biodiversity and landscape quality in urban areas and the implementation of the ecological compensation, aimed at assisting cantons and municipalities (BAFU, 2023b, issued for the first time in 2022).

In the specific domain of heat adaptation in urban settings, a study focusing on Swiss cities' administrations' perspectives revealed that many local authorities would welcome greater support from both cantons and local legislative bodies (Fujara, 2022). A large majority of cities and towns recognize the increasing strain that heatwaves put on urban areas and deem it an urgent issue. However, only 17% of the cities (mainly large and medium-sized ones) have strategies dedicated specifically to heat adaptation. According to the FOEN, those are mainly cities with strong administrative structures under progressive political influence (Representative of FOEN, personal communication, April 17, 2025). These strategies include support tools or regulatory measures that aim to encourage the greening of private properties and climate adaptation of public spaces. About one-third of the cities lack a strategy altogether. The remaining municipalities have integrated heat adaptation into their broader climate strategies.

One of the earliest regulatory policies involving NBS at the municipal level is the requirement to green flat roofs on newly constructed buildings—sometimes extending this obligation to renovations. Zurich introduced this regulation in 1991, while Basel followed in 1999. The policies include guidelines on the height, mass and profile of the substratum, and on the species of plants. There are stricter demands for extensive roof greening in large projects, which have special building policies (Stadt Zürich, n.d.-b). Today, most municipalities in Switzerland have similar regulations requiring the greening of flat roofs (Wepf, 2016).

5.3 Size and role of the market

Rather than ushering the adoption of NBS, the market's lack of interest appears to hinder progress. This can be seen in the various examples where the implementation of nature-based measures was slowed down by other market interests.

One relevant market factor pertains to the obligation to green flat roofs. A recent study of Zurich's flat-roof greening initiative found that, in the 1990s, the percentage of green roofs increased from under 20% to over 25%. However, since the 2000s, this percentage has
steadily declined, with only slightly more than 10% of newly constructed flat roofs being green between 2011 and 2015 (Kübler, 2024). This decline is attributed to increasing competition for roof space, as many building owners use the upper floors for terraces or penthouse apartments, which add value to the property but reduce available space for greening.

Another example is the sponge city concept (Schwammstadtkonzept), an urban planning principle that aims at rainwater retention instead of drainage, which is currently being tested in several pilot projects. As a NBS, it aims to improve urban climate and is even supported by some municipalities (e.g. Zurich) through incentives for unsealing private land. However, it is technically challenging to implement in existing residential areas and economically unattractive, as it tends to hinder rather than encourage construction. According to a FOEN representative, the lack of market appeal is one of the reasons why NBS do not have a strong lobby and are not prioritized politically (Representative of FOEN, personal communication, April 17, 2025).

Furthermore, the challenge with NBS for real estate investors lies in their limited measurability and quantifiability, which makes it difficult to incorporate their value into property pricing (Interview CM). If the costs of such investments cannot be recovered through higher rents, profit-oriented landlords have little incentives to adopt these 'soft factors', as stated by a real estate investor to FOEN: "For these (factors) to be considered serious criteria for developing a property portfolio, they must be more measurable" (Representative of FOEN, personal communication, April 17, 2025).

<table><caption>Table CH4. Examples for NBS measures in Switzerland.</caption><thead><tr><td>NBS Measure</td><td>Policy / Example</td></tr></thead><tbody><tr><td>Greening of flat roofs</td><td>Mandatory in Zurich since 1991 and currently mandatory in most municipalities</td></tr><tr><td>Sponge City Principle</td><td>Pilot projects in several municipalities (Bern, Lucerne, Zurich...), Municipal subsidy programmes for unsealing private land</td></tr><tr><td>River Renaturation</td><td>Water Protection Act, National subsidy programme</td></tr><tr><td>Increase of Tree canopy area</td><td>Tree protection, Municipal subsidy programmes for heat reduction</td></tr><tr><td>Renaturation of large-scale infrastructure (grey to green)</td><td>Project-based public funding, e.g. Schwamendingen (Zurich): Enclosure of highway with park on top</td></tr></tbody></table>

## 5.4 The multilevel governance process

Sections 4.1 and 4.2 have highlighted that the development of NBS-related policies are relatively recent that gained momentum only over the past decade. While environmental organizations, particularly in the area of biodiversity, have exerted significant pressure, movements like Fridays for Future, which started in Switzerland in December 2018, have contributed to increasing the pace of policy development related to climate change mitigation
and adaptation (Schweizerischer Städteverband et al., 2024). However, resources allocated at the national level remain limited (as criticised regarding the Actions Plans for biodiversity; Pro Natura et al., 2024), with implementation largely expected to occur at the municipal level. This means that the success of these initiatives depends primarily on local stakeholders—whether government officials, administrators, local parliamentarians, or civil society organisations (Braunschweiger & Pütz, 2021).

As a result, some cities are leading the way with innovative strategies and implementations, while smaller towns often lack a clear strategy altogether (Schweizerischer Städteverband et al., 2024). This disparity may also reflect political orientation, as progressive parties tend to support NBS and related strategies, whereas liberal-conservative parties often oppose them, citing concerns about high costs and negative impacts on sectors such as agriculture, energy, and tourism.

Municipalities can implement NBS on public land, for example by greening municipal buildings, planting trees along roads, or undertaking river restorations. However, expanding the presence of green roofs and facades mainly depends on the willingness of private property owners. To this aim, many cities offer incentives, such as subsidies and free consultations, and have incorporated the greening of flat roofs into building regulations (Wepf, 2016).

A notable example of a municipal program promoting both heat reduction and biodiversity is the *Stadtgrün* initiative by the City of Zurich, which began in 2024 and will run until 2035. The programme consists of four sub-programmes targeting different stakeholders: the first supports green measures in public spaces and streets; the second offers advice and subsidies to private property owners; the third promotes green measures on municipal properties; and the fourth funds research and pilot projects on heat reduction (Stadt Zürich, 2024b). The program has a total budget of 130 million Swiss Francs, with 28.2 million allocated to the second sub-programme for private property owners between 2024 and 2029 (Stadt Zürich, 2024c).

At the national level, the Grünstadt Schweiz (Green City Switzerland) label promotes urban greenery and sustainable management of green spaces. This label, founded and managed by the Association of Swiss Departments for Green Spaces since 2017 (Verband Schweizerischer Stadtgärtnereien und Gartenbauämter, VSSG) and partially funded by the FOEN, is awarded to cities committed to urban greening. Up to date, 20 cities have received the Grünstadt label, with 7 more in the certification process.
<table><caption>Table CH5. Actors involved in the policy cycle of NBS.</caption><thead><tr><td>Sector</td><td>Level of governance</td><td>Name</td><td>Role/Responsibilities</td><td>Date of appearance</td></tr></thead><tbody><tr><td>Public</td><td>National</td><td>Federal Office for the Environment (FOEN)</td><td>Elaboration of NBS strategies and action plans at national level</td><td>1971</td></tr><tr><td>Public</td><td>Cantonal</td><td>Cantonal offices for the environment</td><td>Elaboration of NBS strategies and action plans at cantonal level and implementation with cantonal boundaries</td><td>depending on Canton</td></tr><tr><td>Public</td><td>Cantonal</td><td>Cantonal offices for the spatial development/construction</td><td>Regulation of greening obligations and compensation areas through planning and building regulations</td><td>depending on Canton</td></tr><tr><td>Public</td><td>Municipal</td><td>Municipal offices for the environment</td><td>Elaboration of NBS strategies and action plans and their implementing at local level</td><td>depending on municipality</td></tr><tr><td>Public</td><td>Municipal</td><td>Municipal offices for the spatial development/construction</td><td>Regulation of greening obligations and compensation areas through planning and building regulations</td><td>depending on municipality</td></tr><tr><td>Non-governmental organisation</td><td>National</td><td>WWF Schweiz</td><td>Promotion of biodiversity through NBS</td><td>1961</td></tr><tr><td>Non-governmental organisation</td><td>National</td><td>BirdLife</td><td>Promotion of biodiversity through NBS</td><td>1922</td></tr><tr><td>Non-governmental organisation</td><td>National</td><td>Pro Natura</td><td>Promotion of biodiversity through NBS</td><td>1909</td></tr><tr><td>Non-governmental organisation</td><td>National</td><td>Swiss Fishing Federation</td><td>Promotion of biodiversity through NBS</td><td>1883</td></tr><tr><td>Non-governmental organisation</td><td>National</td><td>Swiss Farmers' Union</td><td>Opposition to NBS entailing transition from intensive land cultivation to extensive uses</td><td>1897</td></tr><tr><td>Non-governmental organisation</td><td>National</td><td>+ others</td><td></td><td></td></tr><tr><td>Non-governmental organisation</td><td>National</td><td>Grünstadt Schweiz (under the responsibility of the Association of Swiss Departments for Green Spaces (Verband Schweizerischer Stadtgärtnereien und Gartenbauämter VSSG, partially funded by the FOEN))</td><td>Certification of cities with formal commitment to urban greenery</td><td>2012</td></tr><tr><td>Private</td><td>Municipal</td><td>Private landowners</td><td>Implementation of NBS (greening of roofs/facades, de-sealing)</td><td></td></tr></tbody></table>
5.5 Assessments, achievements and challenges

Given the lack of a policy specifically defining and promoting Nature-Based Solutions (NBS), there has been no targeted evaluation or research focusing on their implementation or overall impacts. According to FOEN and SFOE representatives, the national agenda focuses on climate adaptation strategies with measurable goals, such as achieving net zero by 2050 (Representative of FOEN, personal communication, April 17, 2025) (Representative of SFOE, personal communication, May 8, 2025). The focus on climate adaption rather than biodiversity measures was also reflected in the popular vote in 2024, when the Biodiversity Initiative was rejected. Switzerland's policies are influenced by the powerful farmers' lobby that favours biodiversity measures concentrated in urban and residential areas. As a result, no federal subsidy programme has been established. In rural areas, biodiversity measures are rare and are usually implemented and subsidised by the cantonal authorities, since small municipalities often lack the resources and expertise to implement such complex concepts.

The varying degrees of progress in the greening of municipalities of different sizes are also reflected in the Greencity certification (Representative of Grünstadt Schweiz, personal communication, April 15, 2025). **Nature-based solutions (NBS) are not only complex and costly to implement, but their adoption is also hindered by political tensions—particularly between national strategic goals and the resistance from conservative governments.** To date, there has been no mandatory ecological planning at a municipal level, meaning that local legislation and subsidy programmes are highly diverse (Martinoli et al., 2025).

One notable aspect of the Swiss situation is the absence of public or academic discourse around issues of distributive justice related to green spaces and greening subsidies. There is little debate regarding the impact of creating or upgrading green spaces on property values and housing costs, nor is there significant discussion about where and for whom green spaces are developed. **The implementation of NBS varies significantly depending on whether the land is privately or publicly owned, particularly in terms of the stakeholders involved, funding mechanisms, and resulting impacts.** In public spaces, green interventions tend to influence rent and property prices only after several years, making it difficult to establish a direct correlation. Moreover, Swiss tenancy law has yet to clarify whether NBS can be legally considered value-enhancing measures that would allow rent increases. As a result, further research is needed to understand whether and how NBS affect housing affordability. Additionally, the unequal effects of subsidies for greening private roofs, facades, or gardens—particularly on homeowners versus tenants— have not been addressed by public debates and research yet.

<table>
   <thead>
    <tr>
     <td>
      Policy / Programme
     </td>
     <td>
      Measured impacts on housing inequalities
     </td>
     <td>
      Potential impacts on housing inequalities
     </td>
    </tr>
   </thead>
   <tbody>
    <tr>
     <td>
      Municipal Subsidies for NBS (e.g. Stadtgrün ZH)
     </td>
     <td>
      -
     </td>
     <td>
      Unequal Access: Only Property owners benefit from subsidies.
     </td>
    </tr>
   </tbody>
  </table>
<table><caption>Table CH6. Summary table of measured and potential impacts of NBS policies on housing inequalities.</caption><tr><td></td><td></td><td><strong>Green Gentrification:</strong> Large-scale greening projects can lead to rent increases and displace existing residents.</td></tr><tr><td>Certifications by Grünstadt Schweiz</td><td>-</td><td>Green Gentrification through location improvement</td></tr><tr><td>Green Building Policies (e.g. Greening of flat roofs)</td><td>-</td><td>Higher rents because increasing construction costs can be passed on to tenants</td></tr></table>

# 6 Densification

## 6.1 The policy cycle: emergence of the issue and policy decisions

Given Switzerland's scarcity of buildable land (see section 2.1), it is not surprising that land use regulations, directly or indirectly aiming at densification, already began emerging after the 1960s construction boom, focusing initially on controlling pressure on agricultural land and later on landscape protection and biodiversity conservation, as stipulated by the Federal Constitution (Art. 2 CSC). Areas like natural monuments and historic pathways are regulated by the Federal Act on the Protection of Nature and Cultural Heritage (Bundesgesetz über den Natur- und Heimatschutz, NHG), which was passed in 1966.

In 1979, a national vote led to the incorporation of spatial planning principles into the Federal Constitution. The first Spatial Planning Act (SPA; Raumplanungsgesetz, RPG) introduced dynamic structural and use planning by assigning spatial responsibilities and effective tasks to the regions and municipalities. It aimed at distinguishing building and non-building areas, without initially emphasizing densification. The Swiss Federal Office for Spatial Development (Bundesamt für Raumentwicklung, ARE/SFOSD), created in 2000, coordinates sustainable development, balancing compact settlement, landscape protection, and land use across the 26 cantons.

Despite these regulations, urban sprawl continued into the 2000s. With the spatial development report (Raumentwicklungsbericht), the SFOSD published a self-critical assessment which found that spatial development in Switzerland is unsustainable and asked for a holistic spatial development concept and a revision of the SPA (Represenative of SFOSD, personal communication, May 20, 2025). This prompted the 2008 Landscape Initiative (Landschaftsinitiative) which called for a 20-year freeze on building zones and the promotion of inner-city development by the federal government and the cantons (ARE, 2024b). In response, the Federal Council proposed a thorough revision of the SPA, introducing densification as a legally binding policy and restricting land hoarding. The revision was approved by a large majority of voters in 2013. The SPA I, which came into force in 2014, can
be seen as a turning point in Swiss spatial planning, with significant requirements for densification and land conservation through the strict regulation of building zones.

In parallel, the non-binding Swiss Spatial Concept (Raumkonzept Schweiz), launched in 2012, seeks to harmonise the objectives of the cantons and municipalities. It aims to guide development with a focus on sustainable urban planning, mobility and regional diversity. The Swiss Biodiversity Strategy, adopted in 2012, stresses integrating biodiversity into spatial planning and promoting biodiversity within settlement areas (Bundesrat, 2012). Additionally, the Second Home Law (Zweitwohnungsgesetz, ZWG), which was approved by Swiss voters in the same year, limits the construction of vacation residences to preserve land, protect the character of existing settlements and increase use density.

Despite these efforts, settlement areas expanded by 31% between 1985 and 2018, consuming large amounts of agricultural land (BFS, 2021). In response, the Green Party launched a popular initiative against urban sprawl (Zersiedlungsinitiative), demanded further limitations on building zones and emphasized small-scale settlement (ARE, n.d.). It was rejected by the Swiss voters in 2019. The second landscape initiative, which followed shortly afterwards, again called for measures against urban sprawl, the protection of building-free zones and the prevention of the conversion of agricultural buildings (ARE, 2024b). This prompted the Federal Council to counter-propose the second revision of the SPA, which focuses on regulating construction outside designated zones. It was approved by the Swiss parliament in 2023 and will soon be implemented.

In 2020, the Landscape Concept Switzerland (Landschaftskonzept Schweiz, LKS) was adopted to ensure the cultural quality in landscape development. Furthermore, the Swiss Soil Strategy (Bodenstrategie Schweiz) was introduced to limit construction activities and to protect land as a non-renewable resource. In line with the EU Soil Strategy 2030 aiming at ceasing land consumption by 2050 both are legally binding (BAFU, 2024). These recent initiatives highlight the growing urgency of densification and land preservation in Switzerland, marking a shift towards a more concrete implementation of these goals. Today the share of undeveloped building zones in Switzerland as a whole is 10 to 16%, with the largest part being urban areas at 46%, while peri-urban and rural areas have similar ratios at 29% and 25% respectively (ARE, 2022).
<figure><img src="image_95.png" /><figcaption>Figure CH30. Timeline of policies, initiatives and strategies affecting densification goals in Switzerland.</figcaption></figure>

6.2 The implementation process

Due to Switzerland's federalist structure the implementation of densification objectives has been rather slow, with meaningful influence on local planning becoming visible only a decade after the introduction of the first revision of the SPA in 2014. In fact, the principle of subsidiarity grants significant authority in spatial planning and thus in the implementation of densification goals to local governments.

While the federal government sets legal frameworks, broad concepts and strategies (Konzepte und Sachpläne), such as the SPA and the Spatial Planning Concept, the cantons are required to align their regional structure plans (Richtpläne) with these national directives. These plans, typically spanning 20-25 years, focus on land use in urban areas, landscapes, transport, and infrastructure (ARE, 2024c). Cantons must allocate building land based on demographic forecasts, adjust building zones to protect agricultural land, and ensure that any increase or decrease in land value due to new zoning is compensated. Specifically, 20% of the added value from new building rights must be deducted (Art. 5 SPA). Zoning was only possible until all cantonal structure plans had been approved by the federal government, which is why there is an absolute freeze on building zones from 2019.

Municipalities play a key role in guiding and executing local densification efforts through utilization plans (Nutzungspläne). These plans often integrate various planning instruments, such as planning zones, which serve as a precursor to relocating and rezoning building land. Densification strategies target a range of sites, including brownfields, greenfields, underutilized building zones, gaps between structures, and urban wastelands in easily accessible locations.
Priority is given to fully utilizing these resources before implementing rezoning measures, which may involve transforming or replacing the existing housing stock (ARE, 2019).

Beyond issuing building permits, municipalities are now tasked with ensuring the realization of dense, high-quality settlements. In many cantons, municipalities must concretize structure plans by developing settlement concepts and establishing minimum density requirements for building zones. These new responsibilities require expertise in development and process management. Utilization plans must strategically address the impacts of densification on living quality, ensuring they are both practical and compelling.

Some municipalities have taken proactive steps to institutionalize densification as a planning objective. For instance, the city of Zurich adopted densification as a legally binding planning goal in 2016 to promote sustainable urban renewal. To this aim, the City Council introduced innovative planning tools, such as designated densification zones (*Verdichtungszonen*), which offer developers economic incentives like density bonuses (Zürich Amt für Städtebau, 2013).

The process of adapting local legislation to the national densification policy is not as advancing in municipalities at the same pace: while large cities have administrative power and political influence, smaller municipalities often lack the resources and expertise to implement federal policies. As a result, in 2024 only 43% of the municipalities completed their structure plan adaptation (UVEK & ARE, 2024). According to the head of EspaceSuisse, no general regional differences in the implementation of SPA I can be identified (Representative of EspaceSuisse, personal communication, March 24, 2025). Whereas larger cities feature complex urban fabrics and limited building land reserves, smaller towns often lack the political backing and strategic housing policies needed to implement densification projects. According to a representative of EspaceSuisse, the severity of the housing crisis in larger cities can be attributed to a slowdown in building activity due to the new conditions under the revised SPA, and by the heated housing markets driven by international investors.

Swiss citizens by and large support the SPA I, but local acceptance of densification projects can be challenging, particularly in existing neighbourhoods due to the NIMBY (Not In My Backyard) effect. For projects to gain public approval, they must demonstrate clear social and ecological benefits that enhance the quality of the affected neighbourhood (UVEK & ARE, 2024). Without such benefits, Swiss voters have the power and are likely to block essential planning tools for densification, such as special land-use plans (*Sondernutzungsplan*).
<figure><img src="image_96.png" /><figcaption>Figure CH6. Spatial planning instruments according to the Federal Law on Spatial Planning (source: SFOSD, 2012; own translation).</figcaption></figure>

<table><thead><tr><td>Form</td><td>Level of governance</td><td>Name</td><td>Aim</td><td>Date of appearance</td></tr></thead><tbody><tr><td>Law</td><td>National</td><td>Nature and Cultural Heritage Protection Act (NHG)</td><td>Secures the protection and conservation of biodiversity, heritage landscapes, sites of local character, historical sites, natural and cultural monuments.</td><td>1966</td></tr><tr><td>Inventory</td><td>National</td><td>Federal Inventory of Heritage Sites of national importance (ISOS)</td><td>Inventory of townscapes and settlements with significant cultural value that should be protected (ca. 1250 objects).</td><td>1970</td></tr><tr><td>Inventory</td><td>National</td><td>Federal inventory of landscapes and natural monuments (BLN)</td><td>Inventory of the most valuable landscapes and natural monuments of Switzerland (162 objects).</td><td>1977</td></tr></tbody></table>
<table><tr><td>Inventory</td><td>National</td><td>Federal inventory of historic pathways and transport routes (IVS)</td><td>Inventory of valuable historic transport routes of Switzerland (3'750 km).</td><td>1883</td></tr><tr><td>Law</td><td>National</td><td>Spatial Planning Act (SPA)</td><td>Aims to ensure sustainable land use by coordinating urban development, environmental protection, and infrastructure planning. It seeks to balance development needs with the preservation of natural resources and quality of life across the country.</td><td>1979</td></tr><tr><td>Initiative</td><td>National</td><td>Second Home Initiative</td><td>Aimed at limiting the share of vacation homes per municipality and was accepted by the majority of Swiss voters in 2012 (see below)</td><td>2007</td></tr><tr><td>Initiative</td><td>National</td><td>Landscape initiative (Landschaftsinitiative - Raum für Mensch und Natur) (withdrawn)</td><td>Aimed to introduce densification as a legally binding policy objective. It proposed that building zones should cover no more than the demand for the next 15 years, and that oversized building zones should be reduced or moved to other locations.</td><td>2008 - 2013</td></tr><tr><td>Strategy</td><td>National</td><td>Spatial Concept Switzerland</td><td>Outlines the country's long-term spatial planning strategy, focusing on balanced regional development, sustainable land use, and the efficient integration of transportation, housing, and environmental conservation.</td><td>2012</td></tr><tr><td>Law</td><td>National</td><td>Second Home Law</td><td>Bans the construction of new vacation apartments and the use of over 20% of existing apartments per municipality as second homes with the aim of preserving the character of existing settlements and increase their density of use.</td><td>2012</td></tr><tr><td>Strategy</td><td>National</td><td>Swiss Biodiversity Strategy</td><td>Promotes biodiversity within settlement areas to ensure that they contribute to the networking of habitats, to the preservation of settlement-specific species, and provide</td><td>2012</td></tr></table>
<table><tr><td></td><td></td><td></td><td>people opportunities to experience nature in their living environments and local recreational areas.</td><td></td></tr><tr><td>Law Revision</td><td>National</td><td>SPA I (1. revision of the SPA)</td><td>Compared to the previous version, the revised law introduced stricter controls on building zones, emphasized the protection of open spaces, and focused on directing urban development to already built-up areas, aiming to ensure more efficient and environmentally conscious land use.</td><td>2014</td></tr><tr><td>Action Plan</td><td>National</td><td>Biodiversity Action Plan</td><td>Conserve biodiversity by serving as an interface between the Confederation's biodiversity policy and other policy areas, including agriculture, spatial planning, transport, and economic development.</td><td>2017</td></tr><tr><td>Initiative</td><td>National</td><td>Initiative against urban sprawl (Zersiedlungsinitiative) (rejected)</td><td>Launched by the Young Green Party. It demanded a total freeze of the building zones in Switzerland and that new building zones could only be created if an area of at least the same size had been removed as a building zone elsewhere.</td><td>2019</td></tr><tr><td>Strategy</td><td>National</td><td>Landscape Concept Switzerland</td><td>With the aim of preserving and enhancing diverse landscapes it defines the framework for their coherent and quality-based development. It encompasses 14 landscape quality objectives that provide a framework to support landscape-related stakeholders at the federal, cantonal, and municipal levels with the aim of integrating landscape protection into spatial planning processes, fostering ecological, social, and economic cohesion across the country</td><td>2020</td></tr><tr><td>Strategy</td><td>National</td><td>Swiss Land Strategy</td><td>In the framework of the 2050 climate net zero goal it aims at ensuring that no more land</td><td>2020</td></tr></table>
<table><caption>Table CH7. Policies, initiatives and strategies influencing spatial planning and densification.</caption><tr><td></td><td></td><td></td><td>shall be consumed in Switzerland beyond 2050</td><td></td></tr><tr><td>Initiative</td><td>National</td><td>2. Landscape initiative (2. Landschaftsinitiative) (withdrawn)</td><td>Called for stricter measures to prevent urban sprawl, the protection of landscapes from construction and the prevention of conversion of agricultural buildings</td><td>2020</td></tr><tr><td>Law Revision</td><td>National</td><td>SPA II (2. revision of the SPA)</td><td>Was developed by the Parliamentary Committee for the Environment, Spatial Planning and Energy (UREK) as a counterproposal to the "Landscape initiative" of 2020 and was unanimously approved by the Parliament in 2023. Its aim is to stabilise the number of buildings and the sealed area outside the building zone.</td><td>2023</td></tr></table>

## 6.3 Size and role of the market

The combination of restrictive building zones and low interest rates in Switzerland has sparked a construction boom and driven up land prices, especially in urban areas (BFS, 2021). This trend is primarily fuelled by two factors: a dwindling land supply and increasing demand are causing the housing market to heat up. Additionally, rezoning in certain areas triggered urban renewals and refurbishments of the building stock. Rezoning often entails enhancing accessibility, infrastructure, and the overall quality of neighbourhoods, making these areas more attractive to both residents and businesses. Large-scale rezoning projects, such as those involving entire districts, trigger construction, create jobs, and stimulate local economies. Such economic productivity reinforces densification trends and attracts investors seeking to capitalize on anticipated appreciation, further intensifying demand and development in these urban areas.

For example, the city of Zurich, after years of population decline due to suburbanization, is experiencing a renewed population growth since the late 1990s, partly driven by the influx of highly skilled, high-income migrants, primarily from other European countries (Stadt Zürich, n.d.-a). The redevelopment of former industrial zones entailed large projects that gave a strong boost to the building industry.

Switzerland already has one of Europe's most expensive real estate markets, with Zurich, Geneva, and Basel leading the way. Its robust economy has supported consistent demographic and economic growth. According to a 2023 study by the Federal Office of Housing (BWO, 2023), spatial planning plays a crucial role in shaping housing costs by determining how flexibly the housing supply can respond to shifting demand: Property values
rise most sharply in areas where available building land is scarce. Wüest Partner (2024) further report that the ongoing shortage of rental housing is both caused by rents and transaction prices for owner-occupied properties.

While this increased demand makes urban property highly attractive to investors, it also opens the door to speculation, pushing up land prices and rents. The disparity in rental prices in Zurich, for example, ranges from CHF 15/m² to CHF 55/m² (Lutz et al., 2023). High property values are attracting investors and fuel speculation, which might lead to volatility. According to an expert, investments are primarily driven by the financial sector, as the Swiss property market is regarded as a safe haven for capital (Represenative of SFOSD, personal communication, May 20, 2025). Within the high price segments, public-private partnerships (PPP) are increasingly being adopted to finance large-scale urban redevelopment projects designed to support densification (discussed further below).

From an economic standpoint, Swiss spatial planning in urban areas presents both opportunities and challenges. Rising land values make urban development an attractive target for investments and speculation. These may align with the national densification goals and give a boost to the economy. However, densification often triggers socioeconomic changes, particularly in terms of housing affordability. Although densification may increase the housing supply, it generally entails higher rents due to rising land prices and the renovation of buildings to higher standards. Consequently, market-driven densification often favours higher-income residents, increasing building density without necessarily improving occupancy density. Moreover, higher rents diminish disposable income, reducing purchasing power for many residents.

A similar problem has emerged in tourist areas, where municipalities are experiencing a housing crisis fuelled by the prevalence of second homes and capital investments in underutilized properties. As stated a representative of SFOSD, "There is no shortage of housing in these regions but too little that is affordable for the local population" (Represenative of SFOSD, personal communication, May 20, 2025). Furthermore, rural cantons depending on tourism, such as for example Valais, are not in favour of densification, as could be seen in the popular vote in 2013 (Figure CH31). The focus on growth in cities can lead to opposite developments In rural areas: limited land reserves and a growing rural exodus can leave some remote areas behind by further concentrating development and resources in urban centres (Zufferey, 2020).
Bundesgesetz über die Raumplanung, Abstimmung vom 03.03.2013

<figure><img src="image_97.png" /></figure>

Figure CH31. Distribution of votes on the SPA revision in 2013. Source: BFS – Statistik der Wahlen und Abstimmungen © Bundesamt für Statistik, ThemaKart, Neuchâtel 2010–2020.

6.4 The multilevel governance process

The Swiss Spatial Planning Act (SPA I) aims to coordinate spatial activities across different government levels to promote denser construction. However, implementation varies locally, influenced by cantonal structure plans, planning culture, financial capacity, municipal strategy, and political orientation. Experts view Switzerland's federal structure as a barrier to an effective densification, as regions—despite playing a key role in local spatial development and having the potential to support smaller municipalities—lack formal planning authority (Representative of ETHZ SPUR, personal communication, June 4, 2025).

A report by the SFOSD on factors constraining densification (ARE, 2019) shows that these often result from conflicts between different administrative levels as well as tensions with private individuals. Building codes and land use regulations might hinder the national densification aims, as they regulate distances in between buildings or the usage of strategically important areas (ARE, 2019). Furthermore, regulations of townscape images and landscape heritage can be in conflict with the objectives of the SPA. Besides the legislation of land use planning and cantonal townscape preservation, information and recommendations by the
applicable federal heritage protection inventories<fnref n="175" /> have to be considered as well. For each
case, a holistic coordination process is required to reach an overarching spatial concept. As a
basic planning tool, ISOS is often used to challenge building projects and can constitute a
major obstacle to densification. However, it is argued that if applied in line with the SPA it could
help to increase public acceptance and the spatial quality of urban developments (ARE, 2016).

Private land hoarding in development zones is common in densifying areas. Accordingly, cantons are required to implement land mobilization measures, by introducing time limits for development. Direct democracy in Switzerland allows citizens to influence legislation, making it crucial to anticipate objections. To mitigate these risks, the SFOSD suggests the adoption of participatory planning processes and an early involvement of all stakeholders as a means to avoid conflicts (ARE, 2019). Municipalities also use tools like special land use plans (Sondernutzungsplan) to prevent objections and integrate dense settlements effectively (EspaceSuisse, 2020). Cantons have also introduced instruments to address land ownership issues and achieve densification goals (ARE, 2019).

Regarding horizontal governance, there is broad support for stopping urban sprawl across
various political perspectives. The debate over preserving (agricultural) land and natural
heritage often engages conservative groups, linking land use to national identity and tourism.
Meanwhile, climate-conscious movements advocate densification for social and ecological
reasons. Right-wing (SVP), liberal (FDP, GLP), and conservative (CVP) parties tend to be
more sceptical of densification, while the Green Party (Grüne) and the Social Democrats (SP)
are generally in favour (M. Gerber et al., 2024).

63% of households in Swiss cities live in apartments owned by the private sector, including firms, banks, insurance companies, and pension funds (Debrunner & Hartmann, 2020). To align private profit motives with public densification goals, municipalities offer incentives like densification bonuses. However, competition in the building market means private actors retain significant power, with public-private partnerships (PPPs) facilitating collaboration between municipalities and investors. Depending on local regulations, these dynamics may lead to high profit margins with significant social costs, as observed in Zurich, or lead to more modest returns and a comparatively stable housing market, as in the case of Geneva (Representative of SFOSD, personal communication, May 20, 2025).

<footnote n="175">¹⁷⁵ The three inventories Federal Inventory of Landscapes and Natural Monuments (Bundesinventar der Landschaften und Naturdenkmäler von nationaler Bedeutung, BLN), Inventory of Swiss Cultural Heritage Sites (Bundesinventar der schützenswerten Ortsbilder der Schweiz von nationaler Bedeutung, ISOS), and Inventory of Historic Pathways and Transport Routes (Bundesinventar der historischen Verkehrswege der Schweiz, IVS) are part of the NHG and aim at the preservation of cultural and natural monuments in spatial planning.</footnote>
<table><thead><tr><td>Sector</td><td>Level of governance</td><td>Name</td><td>Role</td><td>Date of appearance</td></tr></thead><tbody><tr><td>Nation-wide association</td><td>National</td><td>VLP<br>Espace Suisse</td><td>Swiss association for Spatial Planning<br>Works for the federation in questions of spatial planning as educator, consulting</td><td>1943</td></tr><tr><td>Public</td><td>national</td><td>Federal Department of the Environment, Transport Energy and Communications, DETEC (UVEK)</td><td>Responsible for infrastructure and environment, hence spatial planning issues.</td><td>1848</td></tr><tr><td>public</td><td>national</td><td>Federal Office for the Environment, FOEN (BAFU)</td><td>Ensures sustainable use of natural resources such as soil, water, air, tranquillity and forests</td><td>1971</td></tr><tr><td>public</td><td>national</td><td>Swiss Federal Office for Spatial Development (ARE)</td><td>Federal authority responsible for spatial planning, mobility policy and sustainable development.</td><td>2000</td></tr><tr><td>public</td><td>cantonal</td><td>Cantonal Offices for Spatial Development</td><td>Prepare regional structure plans, allocate and adjust building land and define a land use development strategy in the areas of settlement, landscape, transport and infrastructure for a medium planning interval of 20-25 years.</td><td></td></tr><tr><td>public</td><td>municipal</td><td>Offices for Urban Development</td><td>Concretise the structure plan through utilisation plans, targeting areas for certain use and density goals, issuing building permits, integrating the public</td><td></td></tr><tr><td>NGO</td><td>nationwide association</td><td>Swiss Heritage Protection</td><td>Independent organisation for the preservation of cultural building heritage</td><td>1905</td></tr><tr><td>NGO</td><td>nationwide association</td><td>ProNatura</td><td>Independent nature preservation organisation in Switzerland, e.g. protecting nature reserves, launching initiatives</td><td>1909</td></tr><tr><td>NGO</td><td>nationwide association</td><td>BirdLife</td><td>Independent nature preservation organisation in Switzerland, e.g. protecting</td><td>1922</td></tr></tbody></table>
<table><caption>Table CH8. Actors involved in the policy cycle of densification</caption><tr><td></td><td></td><td></td><td>nature reserves, launching initiatives</td><td></td></tr><tr><td>private</td><td>nationwide association</td><td>Different political parties</td><td>Parties are involved in the proposal of initiatives representing public opinions and if accepted changing the law</td><td>-</td></tr><tr><td>private</td><td>different</td><td>Private landowners<br/>Private investors</td><td></td><td>-</td></tr></table>

## 6.5 Assessments, achievements and challenges

Urban densification has been a key policy goal in Switzerland since the 2014 revision of the Spatial Planning Act. Yet, despite this legal framework, a study by the Swiss Federal Office for Spatial Development (ARE, 2024a) shows that a significant portion of new housing continues to be built on undeveloped land, particularly in rural and peri-urban areas. However, this trend is gradually shifting, especially in cities and tourist regions. From 2018 to 2022, 59% of new dwellings were built on existing sites, often through redevelopment of already built areas (ARE, 2024a). This shift is reflected in the stable building zones from 2017 to 2022, with demographic growth contributing to a reduction in land consumption per capita—from 309 m² in 2012 to 282 m² in 2022. Today, 95% of the Swiss population lives within building zones, of which 10-16% remains unbuilt and available for future development (ARE, 2022). However, according to a researcher, densification in Switzerland is not contributing to sustainable development at the moment: “De facto, more is being built in the form of more building volume, more concrete in the end.” (Representative of ETHZ SPUR, personal communication, June 4, 2025).

With the second revision of the Swiss Spatial Planning Act, densification became legally mandatory and a key priority of Swiss policies (UVEK, 2024). Platforms like densipedia.ch and EspaceSuisse were established to support its implementation. Harmonizing structural conditions across cantons is also a key focus, which sometimes requires complete overhauls of cantonal building laws. By 2022, all 26 cantonal structure plans were accepted by the Federal Council, with municipalities now tasked with land-use planning and the finalization of building zones. However, so far only 43% of municipalities have adapted their land-use plans to meet cantonal structure requirements (UVEK & ARE, 2024). Urban municipalities are generally ahead of their rural counterparts in adopting SPA I, likely due to greater housing demands, more planning resources, and lower public resistance. Nevertheless, for densification to succeed, municipalities must develop new competences to maintain both urban quality and public support. Limited resources often lead municipalities to rely on external experts, which can slow down knowledge transfer and hinder locally adapted solutions. Particularly in rural areas with a high proportion of residential properties, changes to land use plans - such as the rezoning of land - is often causing strong political resistance (UVEK & ARE, 2024).
One of the central challenges of densification is its impact on housing affordability. Critics have argued that the 2014 SPA revision has contributed to rising housing costs, and in some urban areas to gentrification and displacement (Debrunner, 2024). Indeed, between 2000 and 2021, the price of single-family houses increased by 80%, while rents rose by 30%. The mechanisms of Swiss spatial planning, according to an employee of the SFOSD, allow the market to react immediately, depending on the capacity of local regulation to stabilize: "Ultimately, it is always a question of who benefits from regulation and who from non-regulation" (Represenative of SFOSD, personal communication, May 20, 2025). Land rezoning plays a crucial role in facilitating or restricting development and thus the possibility to adapt to the housing shortage. However, densification only alleviates the housing shortage in places where occupancy rates are already exhausted. In general, therefore, the impact of densification depends on the context (BWO, 2023).

Public acceptance remains a crucial factor in the success of densification, as pointed out by multiple studies (J.-D. Gerber & Debrunner, 2022; Herdt & Jonkman, 2023; Sudau & Grêt-Regamey, 2024; Wicki et al., 2022). A media analysis from 2010 to 2019 on gentrification found that public opinion is pivotal to the success of densification projects. While support for densification at the national level has grown to 57.5%, local support remains much lower, at just 11.9% (Wicki et al., 2022). Emotional responses tied to concerns over place identity and personal autonomy often cause resistance, especially in communities close to proposed densification projects (Herdt & Jonkman, 2023). Despite general agreement on the need for more housing, NIMBYism often obstructs local efforts. Researchers suggest that Switzerland's direct democratic tools, if used for site-specific solutions and public participation, could improve the quality and equity of densification (Herdt & Jonkman, 2023). Collaborative efforts between the public and the private sector are seen as essential for achieving socially sustainable densification (Perić et al., 2023).

Critics have also pointed out that private actors, particularly corporate property owners, are the main beneficiaries of densification, often prioritizing financial gains over social justice (Debrunner, 2024). Large-scale projects are typically driven by private entities such as banks, insurance companies, and pension funds. Switzerland's strong property protection laws, which favour property owners, further contribute to rising property values and an imbalance of decision-making power, leaving tenants at a disadvantage (Debrunner, Jonkman, et al., 2024; J.-D. Gerber et al., 2017). This unequal distribution of the benefits of densification has led to growing public resentment. Comparative studies suggest that granting municipalities greater authority to intervene in property rights could lead to more equitable and effective densification outcomes (Götze & Jehling, 2023). A representative of SFOSD criticized the insufficient consideration of the connection between spatial development and real estate market: "I believe the purpose of (spatial) regulation should be (...) to ensure excessive profit opportunities are not offered at the expense of communities or individuals" (Represenative of SFOSD, personal communication, May 20, 2025).

Different densification strategies—such as brownfield developments, transit-oriented developments (TODs), and rezoning—have varied effects on local demographics. For example, it was found that in Zurich, densification efforts have largely been driven by new construction (being 6.5 times more common than refurbishments), leading to the displacement of lower-income residents (Kaufmann et al., 2023). Lutz et al. (2024) also noted that while
TODs increase population density, they tend to displace low-income households near transportation hubs, exacerbating inequality and contributing to gentrification. Similarly, Verheji et al. (2023) explored the challenges of ensuring public access to green spaces in privately managed densification projects.

Currently, no policies specifically address the social impacts of densification: most strategies focus on spatial issues, while socio-economic consequences like displacement and unequal housing conditions are largely overlooked. An expert highlights the construction-oriented focus of current legislation, noting: "If we want to make consistent contributions towards sustainability with the SPA, we must promote use density and mixed uses." (Represenative of SFOSD, personal communication, May 20, 2025). Most densification projects are driven by private developers who view housing primarily as an investment, rather than a social good (Perić et al., 2023).

<table><caption>Table CH9. Summary table of measured and potential impacts of densification policies on housing inequalities.</caption><thead><tr><td>Policy / Programme</td><td>Measured impacts on housing inequalities</td><td>Potential impacts on housing inequalities</td></tr></thead><tbody><tr><td>SPA I</td><td>Displacement of vulnerable groups:<br/>In zones with scarcity of buildable land, densification often replaces older, affordable housing with new developments. (Debrunner, 2024)<br/>In TOD (transit oriented developments), displacement of lower-income residents has been proved (Lutz et al., 2024)</td><td><strong>Rising Costs</strong>: Reduced building zones and land speculation drive up land prices and urban rents.<br/><br/><strong>Ignored Tenant Needs</strong>: Federal policies prioritize inner development and investor interests over tenant protections.<br/><br/><strong>Uneven Capacity</strong>: Small and large municipalities share densification responsibilities but differ in capacity, leading to slower housing delivery and reduced quality.</td></tr><tr><td>Second Home Initiative</td><td></td><td>Rising housing prices, disappearance of affordable housing for local population in tourist areas</td></tr></tbody></table>

# 7 Summary and discussion of results

## 7.1 Summary of changes in EEPs

Also in Switzerland, international policies such as the Kyoto Protocol and Paris Agreement triggered ambitious national climate goals in the early 2000s. With national support, several local governments—especially larger cities—enhanced these goals by launching their own complementary programmes.
As mentioned in Chapter 1, over the last two decades, Switzerland has seen a continuous evolution of environmental and energy policies. Popular initiatives and social movements have played an important role in shaping EEPs, with public opinion capable of both accelerating and impeding political momentum. Although most initiatives aimed at more progressive regulation or stronger climate protection were rejected, they sparked lively public debates and sometimes prompted revisions to legislation.

The Swiss political system not only influences how decisions are made but also leads to considerable variation in regulations across the country. *The subsidiarity principle gives equal responsibility to all municipalities, regardless of capacity, leading to uneven implementation.* Depending on available financial and professional resources, national policies are therefore not implemented uniformly across all municipalities. *Direct democracy can lead to diluted measures in order to gain majority support.* This can lead to approaches deviating from their original objectives or being redirected to serve different agendas. For example, the relatively weak tenant protection law triggers **renovictions as they** enable landlords to carry out extensive renovations and subsequently charge higher rents.

Lobbies are an important part of political decision-making in Switzerland. For EEPs **the conservative farmers' lobby and the liberal building sector have exerted considerable influence, while the homeowners' association (Hauseigentümerverband HEV) plays a key role in shaping housing policies, in particular the tenancy law.** Several representatives from federal organisations agreed that parliamentary decision-making is largely driven by market interests rather than environmental concerns. The real estate sector is fuelling density goals, primarily aiming for higher building density. *The building sector defends the Buildings Programme and promotes densification developments.* Thus, while both energy refurbishments and densification are supported by influential lobbies, NBS lack political support, as the market shows little interest in non-profitable measures provided by nature. Furthermore, the farmer's lobby opposes federal subsidies, as it has no interest in more regulations for agriculture. All experts we in on NBS we could interview explained that biodiversity objectives are of secondary importance to parliament, meaning that funds are preferably channelled into energy savings and decarbonisation. Market interests partly explain the political focus on measurable change and technical responses in the climate debate. Regarding an international real estate market, climate adaptation measures are becoming increasingly important to obtain sustainability certifications that enhance property value.

Switzerland's national policies reflect a strong political focus on energy efficiency, driven by climate goals and energy strategies. The Buildings Programme, with a total budget of CHF 528 million in 2023, has significantly expanded over the past decade making an important contribution to energy savings. National support to energy refurbishments further incentivised cantons to pursue active energy policies and required municipalities to establish structure plans and schemes. However, as stated by the representatives of different federal organisations, there have been considerable budget reductions in all departments. The political orientation of department heads, this can lead to a reduction in funding (Representative of SFOE, personal communication, May 8, 2025).

The term *nature-based solutions* (NBS) has only recently entered public discourse in Switzerland and still lacks a dedicated federal funding scheme—likely due to limited market
interest. To date, municipalities have remained the central actors in regulating, implementing, and promoting NBS, meaning that their success depends entirely on local political will and available resources.

With the enactment of the SPA I revision, densification became a legally binding and central planning objective nationwide. In combination with increased land and real estate speculation, the reduction of designated building zones has been identified as a contributing factor to rising housing costs. **As the implementation of the SPA at the local level has hardly started, these challenges are expected to intensify.**

## 7.2 Relations and trade-offs between EEPs and housing policies

Both energy retrofitting and densification have entered Swiss legislation in the early 2000s and have led to significant impacts on social sustainability overall and the housing sector specifically. **However, NBS are only now beginning to be considered in relation to housing affordability—and so far, only in large-scale greening projects. By outlining the general challenges and effects of EEPs on housing affordability, their broader social impacts become evident.**

The subsidy structure for energy retrofitting in Switzerland (Buildings Programme) is being criticised due to a significant deadweight effect—nearly half of the funds go to projects that would have occurred anyway. Wealthier households disproportionately benefit from these subsidies, raising concerns about social equity. The programme lacks social criteria, focusing solely on technical aspects, which may unintentionally exacerbate inequalities.

Energy retrofitting often leads to rent increases, as landlords can pass on 50–70% of renovation costs to tenants, minus subsidies. This has contributed to a rise in rents and renovictions, especially in urban areas, displacing lower-income tenants and accelerating gentrification. In Zurich, for example, 30% of renovations involved tenant displacement, with new tenants earning significantly more than those replaced. Proposed reforms to align energy and housing policy - such as tying subsidies to tenant protections - have not been implemented at the national level due to concerns over cost, enforceability, and property rights. If well-regulated, retrofitting could mitigate energy poverty, but current retrofitting policies and incentives risk worsening housing affordability for vulnerable populations.

To date, NBS in Switzerland face limited national support, as federal priorities lean towards climate adaptation over biodiversity. Implementation is largely left to cantonal and local levels, where smaller municipalities often lack the capacity to manage complex NBS projects. As a result, progress is uneven and highly localized. The unequal distribution of greening subsidies - favouring homeowners over tenants - remains largely unexamined. There is little public or academic debate on how NBS affect housing costs or who benefits from green space investments. While green interventions in public areas may raise property values, the delay in effect makes it hard to measure their impact on rents. Swiss tenancy law does not clearly define whether NBS qualify as value-enhancing improvements that could justify rent increases.
Following the second revision of the SPA in 2014, when densification became legally binding, reducing land consumption has become a central goal of Swiss spatial planning policy. Due to the Swiss federal structure, the state of implementation varies widely between municipalities. Critics argue that densification primarily benefits private investors, such as banks and pension funds, while tenancy needs are bypassed. Switzerland's strong property rights further reinforce this imbalance, limiting tenant influence and fuelling public discontent. While direct democratic tools could enhance participation and equity, they are not yet systematically used in densification processes.

Multiple studies found that densification leads to rising housing costs, gentrification, and displacement, particularly in urban areas. The effects of densification on the local context, by factors such as vacancy rates and municipal governments' regulatory capacity. Land rezoning plays a key role in shaping development potential, but its benefits are unevenly distributed.

**Currently, national policies prioritize hard densification, often at the expense of ecological and social considerations that could be addressed through more inclusive soft densification strategies.**

The combination of EEPs – **as for example densification targets and the promotion of energy retrofitting** – appears to generate severe social impacts that are require a strong political will to be mitigated. As was mentioned, they trigger large scale demolitions of older but affordable housing. The **Swiss tenancy law limits the right to increase rents following minor upgrades and within ongoing rental contracts, indirectly promoting more extensive renovations or full the full replacement of older buildings, which allow tenant evictions**. Such demolitions are not only problematic from a social perspective; as highlighted by some scholars, **current energy policies do not consider the ecological impact of demolition** (Representative of ETHZ SPUR, personal communication, June 4, 2025)..

The growing number of popular initiatives addressing regulations of housing and affordability underscores the increasing tensions between EEPs and social sustainability. Switzerland's complex administrative and political structure leads to significant variation in regulatory approaches across cantons. **Moreover, strong lobbying interests often shape political decisions, frequently sidelining social concerns.** Yet, these concerns must be meaningfully integrated into both the development of EEPs and housing policy.
8 Glossary

<table><thead><tr><td>Abbreviation (ENG / GER)</td><td>German</td><td>English</td></tr></thead><tbody><tr><td>SFOE / BFE</td><td>Bundesamt für Energie</td><td>Federal Office of Energy</td></tr><tr><td>SFOSD / ARE</td><td>Bundesamt für Raumentwicklung</td><td>Swiss Federal Office for Spatial Development</td></tr><tr><td>FSO / BFS</td><td>Bundesamt für Statistik</td><td>Federal Statistical Office</td></tr><tr><td>FOEN / BAFU</td><td>Bundesamt für Umwelt</td><td>Federal Office for the Environment</td></tr><tr><td>FOH / BWO</td><td>Bundesamt für Wohnungswesen</td><td>Federal Office for Housing</td></tr><tr><td>NHG</td><td>Bundesgesetz über den Natur- und Heimatschutz</td><td>Federal Act on the Protection of Nature and Cultural Heritage Protection</td></tr><tr><td>IVS</td><td>Bundesinventar der historischen Verkehrswege der Schweiz</td><td>Inventory of Historic Pathways and Transport Routes</td></tr><tr><td>BLN</td><td>Bundesinventar der Landschaften und Naturdenkmäler von nationaler Bedeutung</td><td>Federal Inventory of Landscapes and Natural Monuments</td></tr><tr><td>ISOS</td><td>Bundesinventar der schützenswerten Ortsbilder der Schweiz von nationaler Bedeutung</td><td>Inventory of Swiss Cultural Heritage Sites</td></tr><tr><td>BDP</td><td>Bürgerlich-Demokratische Partei</td><td>Conservative Democratic Party</td></tr><tr><td>CVP</td><td>Christlichdemokratische Volkspartei</td><td>Christian Democratic People's Party</td></tr><tr><td></td><td>CO2-Gesetz</td><td>CO2 Act</td></tr><tr><td></td><td>Die Mitte</td><td>Centre</td></tr><tr><td>EAER / WBF</td><td>Eidgenössische Departement für Wirtschaft, Bildung und Forschung</td><td>Federal Department of Economic Affairs, Education and Research</td></tr><tr><td>DETEC / UVEK</td><td>Eidgenössisches Departement frü Umwelt, Verkehr, Energie und Kommunikation</td><td>Federal Department of the Environment, Transport, Energy and Communication</td></tr><tr><td>EKZ</td><td>Elektrizitätswerke des Kantons Zürich</td><td>Electricity Provider of the Canton of Zurich</td></tr><tr><td></td><td>Energie 2000</td><td>Energy 2000</td></tr><tr><td></td><td>Energieartikel</td><td>Energy Article</td></tr><tr><td></td><td>Energiefranken</td><td>Energy Franc</td></tr><tr><td></td><td>Energiegesetz</td><td>Energy Act</td></tr><tr><td></td><td>Energieperspektiven 2050</td><td>Energy Perspectives 2050</td></tr></tbody></table>