Photovoltaics, social housing, substandard housing: what changes with the new simplification decree

Published on July 28 in the Official Journal, decree no. 2026-674 brings together 30 measures concerning, in particular, urban planning, construction, housing, and the environment. For the building sector, it modifies the procedures applicable to photovoltaic projects, the calculation of social housing obligations, and structural assessments of dilapidated buildings.

The Government published in the Official Journal of July 28, 2026 a second "mega-decree" intended to simplify the standards applicable to local authorities and to the action of the State in the territories.

Decree No. 2026-674 of July 27, 2026, includes 30 measures amending, in particular, the Town Planning Code, the Building and Housing Code, and the Environment Code. Most of its provisions are immediately applicable.

This text extends an initial decree of 36 measures published in February 2026, which notably eliminated the requirement for annual draining of municipal swimming pools. It also complements the draft law simplifying regulations applicable to local authorities, adopted by the Senate in June.

A third decree is expected in the fall. "Next fall we will have 140 simplification measures," Françoise Gatel, Minister of Territorial Development and Decentralization, told AFP.

The environmental threshold for photovoltaic projects raised to 3 MWp

The main change for photovoltaic project developers concerns environmental assessment. The decree raises the threshold from 1 to 3 megawatts-peak (MWp) above which a photovoltaic installation is systematically subject to an environmental assessment.

Projects with a capacity between 300 kWp and less than 3 MWp remain subject to a case-by-case review. The environmental authority can therefore still require an impact assessment depending on the location, characteristics, and potential impacts of the project.

Raising the threshold does not exempt installations from other applicable procedures, particularly in the areas of urban planning, biodiversity, land clearing, protected species or connection.

For planning permissions, ground-mounted solar installations with a capacity of less than 3 MWp already require prior notification, except in certain protected areas, pursuant to Article R. 421-9 of the Town Planning Code. The new decree therefore primarily aligns the threshold for systematic environmental assessment with that which already existed for building permits.

The Government estimates that streamlining the processing of these applications will result in annual savings of 465.000 euros for businesses, local authorities and government services.

The prison population removed from the calculation of SRU obligations

The decree also modifies the calculation methods for social housing obligations stipulated by the Solidarity and Urban Renewal (SRU) law. The prison population will no longer be included in the reference population used to determine a municipality's obligations.

This provision particularly concerns municipalities hosting a large penitentiary establishment, whose legal population could be artificially increased by the number of prisoners without the latter participating in the local housing market.

The mayor will be able to commission a structural assessment.

As part of the fight against substandard housing, the mayor will now be able to replace a defaulting owner to have the structural diagnosis of a collective residential building carried out.

This assessment aims to evaluate the building's structural integrity and identify any defects that could compromise the safety of its occupants. The decree also facilitates the recovery, by municipalities and inter-municipal authorities, of expenses incurred on behalf of the owner.

"There are measures that allow for a quantifiable economic gain" and others that are more about "efficiency, responsiveness and restoring the power to act", with "very concrete things for mayors", explains Françoise Gatel.

Criticisms of the environmental consequences

In May, France Nature Environnement denounced "regressions" in environmental law in the various texts on simplification, reindustrialization and development of housing production defended by the Government.

"The simplification we are making is not a removal of all these standards. It is not about preventing democratic appeals but about producing efficiency," Françoise Gatel told AFP.

The minister is therefore advocating a better "balance" of standards, intended to accelerate projects without eliminating control and appeal procedures.