France’s Urban Planning Paradigm: Climate, Land, and Legal Reform

A rapidly evolving legal framework: between climate challenges, land constraints and economic imperatives

Urban planning law has been evolving rapidly for several years, at the crossroads of climate, land-use and economic challenges. Public authorities are seeking to reconcile land sobriety, housing production and ecological transition, while private operators must navigate a complex and dynamic regulatory framework.

In this context, companies, developers, investors, real estate firms, hoteliers and industrial players must integrate legal constraints early in the process to safeguard their real estate projects. France offers a protective framework for investors but requires detailed foresight of authorisation procedures and local urban planning policies.

2024–2025: a pivotal moment for French urban planning law

The years 2024 and 2025 mark a pivotal phase, driven by a major renewal of urban planning documents, the rise of environmental requirements and the adoption of the first bioclimatic Local Urban Plan (PLU) in Paris ‒ an  illustrative milestone in the shift towards a “low-carbon” city.

The new PLUs and intermunicipal Local Urban Plans (PLUi) now incorporate strong climate and environmental objectives: land sobriety, renaturing, stormwater management, greening, ecological corridors, or circularity in the construction sector.

This regulatory transformation is accompanied by a profound shift in the overall model: planning no longer merely aims to regulate urban expansion, but to organise the transformation of the existing built environment, prioritising rehabilitation, redevelopment and the reversibility of buildings rather than urban extension.

In other words, tomorrow’s city will no longer expand: it will recycle, reconfigure and transform itself in place.

The major renewal of urban planning documents

The renewal of urban planning documents represents a major issue for real estate stakeholders. Many local authorities are updating their strategic documents through the adoption of new PLUs and PLUis and integrating land-use sobriety and zero net artificialisation (ZAN) objectives. This update cycle is not a mere technical revision: it fundamentally reshapes programmatic balances, building capacities and development strategies.

In this shifting landscape, land production is becoming more demanding and increasingly conditioned by land-use sobriety objectives. Urban planning documents now include more detailed rules regarding green spaces, soil permeability, density, urban forms, preservation of ecological corridors and the reuse of brownfield sites. Several territories even require proof that no urban recycling alternative exists before any new expansion can be authorised. This logic establishes a paradigm shift: urban extension is no longer the rule, but the exception.

For real estate stakeholders, this renewal requires adjusting strategies. Electoral calendars, public inquiry procedures and revision timelines sometimes make project assessments uncertain. Areas previously buildable may become more constrained, while others long overlooked may re-emerge as opportunities for transformation. Developers and investors must navigate evolving and sometimes inconsistent rules from one territory to another, reinforcing the need for careful planning, legal expertise and dialogue with local authorities.

This regulatory transition also represents opportunities: the priority given to urban reuse enhances innovative redevelopment projects, mixed-use operations, ambitious rehabilitations or hybrid formats combining housing, business activities and services. Operators capable of navigating complexity, crafting flexible structures and demonstrating the environmental relevance of their proposals will gain a real competitive advantage.

The renewal of urban planning documents is therefore not merely an additional constraint: it reflects the structural transformation of urban development. It requires learning to operate within a moving framework but also paves the way for a new generation of projects that are more integrated, more land-efficient and more attentive to the building life cycle.

This dynamic has resulted in increasingly complex legal rules, requiring developers, investors and planners to exercise foresight in order to secure their projects.

Strengthening environmental requirements

Although climate and environmental concerns first appeared in urban planning law as early as 1983, recent years have marked a further shift towards the deeper integration of environmental considerations.

Today, PLUs and PLUis include increasingly detailed climate-related requirements: reducing the carbon footprint of developments, soil permeability, ecological corridors, renaturation and biodiversity, stormwater management, natural ventilation, mitigation of heat islands, bio-based materials and the reuse of construction resources. An urban project must now comply with these climate objectives and may be refused if it fails to do so. Energy performance is no longer an asset but a condition of acceptability.

At the same time, the real estate market is being reshaped by ESG criteria, which have become a decisive filter for investment. Buildings that are not renovated, poorly insulated or unable to reach regulatory thresholds are seeing their value decline ‒ a trend already apparent in the tertiary stock of the Greater Paris region. In contrast, assets with environmental certifications, low energy consumption, low-carbon materials or optimal user comfort are becoming premium properties and attracting greater demand.

This climate shift also has significant operational legal consequences. Converting an existing building now requires extensive technical work: change of use, fire safety, natural daylight, load-bearing structures, ventilation, thermal comfort. The question is no longer simply “Can we transform?” but “Can we transform sustainably, with a controlled carbon impact?” The law explicitly encourages reversibility, reuse and the preservation of existing structures rather than demolition-reconstruction, whose carbon cost is increasingly difficult to justify.

This new regulatory ecosystem creates a form of natural selection:

• energy-intensive buildings become risky “brown” assets, facing depreciation;
• reversible, high-performing, low-carbon buildings become the winners in the market; and
• real estate value shifts from land to the potential for sustainable transformation.

Urban planning is therefore  entering a paradigm in which climate and environmental objectives are no longer additional constraints, but the gateway to securing project approvals and financing.

Adoption of Paris’ bioclimatic PLU (PLU-b)

Since 29 November 2024, the bioclimatic Local Urban Plan of Paris (PLU-b) has been officially in force, marking an unprecedented milestone for a European capital.

The new bioclimatic PLU constitutes one of the most significant urban reforms of recent years.

This regulatory document drives a major transformation of the Parisian urban landscape by reconciling climate ambitions with social considerations. It imposes a rigorous bioclimatic approach for both new constructions and renovations: optimal building orientation, priority use of bio-based materials, substantial reductions in energy consumption, and integration of renewable or recovered energy sources.

The goal is clear: to make Paris more sustainable and more resilient to climate change, while addressing the housing crisis.

The PLU-b directs the future of the capital by prioritising the transformation of existing buildings. Available land is scarce, and the city is dense; the solution is therefore to reuse, upgrade and intelligently densify what already exists. In this spirit, the PLU-b facilitates the conversion of office buildings into housing and identifies numerous plots reserved for this purpose through “housing markers” (pastilles logement). The objective is twofold: to produce more housing ‒ particularly social or affordable housing ‒ and to reduce vacant offices and underused sites.

The environmental dimension lies at the core of the system. Future projects must now integrate more demanding climate criteria: increased greening of parcels, mandatory areas of open ground, when possible, stormwater infiltration, mitigation of heat islands, low-carbon materials and reuse. Bioclimatic design is no longer optional; it is a condition for urban acceptability. Construction for the future requires demonstrating that the project enhances quality of life, user comfort and environmental performance.

Beyond technical requirements, the PLU-b expresses a long-term vision: a city that transforms rather than expands, renovates rather than demolishes, densifies without degrading, and  introduces more green spaces to improve liveability. It signals a cultural transition as much as a regulatory one.

The objective is carbon neutrality by 2050. Projects failing to meet these strengthened standards may be refused a permit. The City of Paris now assesses the bioclimatic performance of proposals and grants authorisations only to those that exceed defined thresholds in key areas such as energy, materials, thermal comfort or vegetation. The PLU-b thus represents a major opportunity for real estate investors seeking alignment with ESG criteria.

In the coming years, real estate developments will have to comply with this approach. Projects capable of combining housing, biodiversity, architectural quality and energy sobriety will fit most easily into the approval process; those replicating past models risk facing significant obstacles. The PLU-b therefore provides new possibilities but also imposes a higher degree of rigour and engineering: more than a regulatory document, it constitutes a roadmap for a greener, more inhabited and climate-resilient capital.

The Paris PLU-b has also significantly expanded the number of reserved sites (pastilles) dedicated to the creation of social housing: over 600 new plots have been added, bringing the total to nearly 947, including office buildings and single-owner properties, notably in the central business district. These markers ‒ visible on the interactive map published by the City ‒ constitute urban planning easements based on Article L.151-41 of the French Urban Planning Code, allowing the municipality to reserve land for a project of general interest.

For property owners, the building may continue to be occupied, rented or sold, but any application for a building permit or prior declaration involving significant works must incorporate the creation of housing, including a proportion of social housing or units under a long-term lease (bail réel solidaire), depending on what the marker requires. If the owner cannot carry out this transformation, they may request that the City acquire the asset through the right of relinquishment (droit de délaissement). The City may also pre-empt the property in the event of a sale.

This mechanism is not new and has already been deemed constitutional, with the right of relinquishment maintaining a minimal balance between public interest and property rights. Legal challenges remain possible through claims of illegality in the context of appeals against planning decisions, but the grounds are narrow: only a manifest error of assessment or the impossibility of creating housing on the plot are likely to succeed. In the context of strong pressure on social housing in Paris, case law is generally restrictive.

Beyond this pastillage practice, the transformation of existing buildings has now become the main driver of housing production.

First, by facilitating the conversion of office stock into residential units: vacant office buildings can become residential hubs, sometimes mixed-use, including services, shops or cultural spaces. This approach addresses a long-observed paradox in Paris: a housing shortage on one hand and under-occupied tertiary stock on the other.

Housing thus becomes the central thread of the PLU-b: producing housing without artificialising soils, densifying without degrading, and renovating without disfiguring. It is a demanding but essential equation. Projects capable of combining environmental performance, user quality and the enhancement of existing buildings will, in the future, be the most readily approved by authorities and the most attractive to residents.

Transformation of buildings/reversibility and new uses

Complexity and opportunity

The real estate market is undergoing profound transformation. The conversion of existing office space into hotels or housing is progressing rapidly, while the logistics sector continues to grow. At the same time, the production of new housing is facing a crisis: rising construction costs and slower permitting procedures are weakening traditional development models.

Faced with these constraints, the market is turning to alternative models: coliving, managed residences, hybrid hotels, shared spaces, integrated services or modular housing.

This shift is facilitated by an evolving urban planning framework, which is now more open to reversible projects and multi-destination permits, enabling the uses of a building to be adjusted more easily over time.

The transformation of existing buildings has become one of the key challenges of contemporary urban policies, amid strong pressure on housing supply, rising office vacancy rates and environmental imperatives. Two recent pieces of legislation clearly advance this agenda: the Daubié Law of 16 June 2025 and the Urban Planning and Housing Simplification Law of 26 November 2025. Together, they mark a genuine paradigm shift in building reversibility and the relaxation of the rules enabling it.

The Daubié Law: reversibility becomes a clearly identified legal tool

The most transformative aspect of the Daubié Law lies in the possibility of issuing a building permit with successive destinations ‒ commonly referred to as a reversible or multi-destination permit. A building may thus be authorised for initial use (for example, offices) while also incorporating, from the outset, the possibility of later conversion to housing, without having to repeat the entire urban planning procedure.

The law also allows municipalities to depart from the PLU on a case-by-case basis to authorise the conversion of buildings to residential use, even where housing was not permitted under the local plan.

It further introduces new possibilities for derogations from the PLU, enabling municipalities to authorize housing even where such use is not provided for in the regulations.

Operationally, the reform also eases the rules governing co-ownership: the conversion of tertiary premises into housing may now be approved by a simple majority under Article 24 of the 1965 Law, whereas the previously required reinforced majority constituted a major obstacle.

The Simplification Law: streamlining, accelerating and transforming

The Simplification Law, adopted on 26 November 2025, complements this initial framework by addressing an issue long raised by practitioners: the removal of procedural blockages.

The legislation makes it easier to amend urban planning documents, allows for broader derogations from the PLU ‒ particularly to convert or upgrade existing buildings ‒ and relaxes the assessment of conformity for existing constructions. A permit can no longer be refused solely because the original building does not comply with certain rules relating to siting or external appearance, which opens up practical possibilities for rehabilitation or rooftop extensions.

The first major feature of this law concerns the transformation of buildings. The elevation or “limited transformation” of an existing building may no longer be refused solely because the original structure does not comply with the PLU (new Article L.111-35 of the Urban Planning Code). This provision offers considerable opportunities for restructuring operations, particularly in dense urban environments.

In the same spirit, the legislator broadens the types of derogations available from PLU rules to promote the creation of housing and public facilities. Projects may therefore be authorised within economic activity zones by departing, where necessary, from rules on site coverage, setbacks, building envelopes or external appearance (Article L.152-6-7). The elevation of buildings completed more than two years earlier may also be authorised to create or enlarge residential units, even where they do not comply with the PLU (amended Article L.152-6). Another provision allows municipalities, through a reasoned decision, to derogate from the PLU in urban or urbanisable zones to develop student housing (Article L.152-6-8). Finally, the law eases parking requirements for properties under a long-term lease (bail réel solidaire) and for housing facilities (amended Article L.151-34).

Taken together, these measures pursue a single goal: facilitating building reversibility. They dovetail with the Daubié Law, which created the multi-destination building permit allowing a building to host successive uses over a 20-year period without filing a new permit, provided these uses were anticipated from the outset. This tool is especially valuable for property companies, institutional landlords or mixed-use developments seeking to integrate evolving-use strategies.

The second pillar of the reform concerns planning authorisations. Applications for modified permits filed within three years of the initial permit will be assessed based on the rules in force at the date of the initial permit, except for safety and public health matters (Article L.431-16).

In addition, an application for a development permit may now cover several non-contiguous plots of land, provided it is submitted by a single applicant and that the project forms a coherent architectural and landscape whole (amended Article L.442-1-3). This change responds to the practical realities of large multi-site or sector-based developments.

On the planning side, the law simplifies procedural architecture: planning documents may now be amended only through revision or modification, reducing interpretative uncertainty when determining the applicable procedure (amended Articles L.143-29 and L.153-31). Certain modifications will no longer require an environmental assessment when they concern a material error or reduce the size of an urban or urbanisable zone (amended Article L.104-3). Public participation may, in some cases, be carried out electronically instead of through a public inquiry (amended Articles L.143-22 and L.153-19). Finally, a single document combining the PLUi and the SCOT may be prepared where their boundaries coincide (Article L.146-1), aligning the two planning scales and strengthening coherence.

The final part of the reform concerns litigation. A presumption of urgency is created for référés-suspension seeking to suspend refusals of planning permission (Article L.600-3-1). The administration may no longer add new grounds for refusal more than two months after a claim has been filed (Article L.600-2 v). The administrative appeal period is reduced to one month (from two) and no longer suspends the litigation period (Article L.600-12-2). Article L.600-1 ‒ which allowed procedural defects to be challenged by way of exception within six months after a planning document entered into force ‒ has been repealed.

Finally, the Constitutional Council struck down new Article L.600-1-1 of the Urban Planning Code, which sought to limit standing to challenge a planning document to persons who had participated in the public inquiry (Decision No 2025-896 DC of 20 November 2025).

Another major innovation is the creation of a legal status for “urban transformation operations,” conceived as a tool to redevelop brownfields, monofunctional zones or obsolete office buildings by allowing an integrated approach to uses, heights, functions and project timelines.

A new framework for housing production

These two laws do not solve every issue —some provisions still await implementing decrees, the precise scope of derogations will depend on how municipalities interpret them, and conversions will always involve technical challenges (eg, structure, natural light, ventilation, accessibility).

But the evolution is clear: a shift from prescriptive urbanism to facilitative urbanism ‒ one that encourages reversibility, shortens timelines and gives project developers more legal levers to upgrade the built environment.

France remains an attractive market, but project success now depends as much on advance planning as on legal security. Players who engage urban planning expertise from the earliest project stages ‒ rather than as a final step ‒ are those best equipped to turn regulatory constraints into development opportunities.

In a context where environmental urgency now meets the social urgency of providing housing, these reforms signal a profound transition: the city of tomorrow will be built through adaptation. This will likely define the core of urban policy for the coming decades.