Week of 1 to 7 September 2026
Legislative, regulatory and case-law review
I. Legislation and regulation
The past week was quiet in the Journal officiel on real estate: the issues of 1 to 6 September 2026 contain no text of general scope on planning, co-ownership or off-plan sales. The regulatory event of the period lies elsewhere, in the entry into force on 1 September of the new structure of energy renovation grants.
Energy renovation: MaPrimeRénov’ narrowed on 1 September 2026
Decree No. 2026-822 of 25 August 2026 amending Decree No. 2020-26 of 14 January 2020 on the energy transition grant (JORF of 27 August 2026) came into force on 1 September 2026, except for point 3 of its Article 2 and point 2 of its Article 3, which applied from the day after publication. It is accompanied by two orders of the same date, one amending the order of 14 January 2020 on the energy transition grant, the other the order of 17 November 2020 on energy savings certificates. Together they substantially reshape the scheme for the rest of 2026.
The so-called « single-measure » track is sharply narrowed: in substance, only the installation of an air-to-water or geothermal heat pump, the removal of a fuel-oil tank and connection to a heating network remain eligible, excluding in particular loft and wall insulation, mechanical ventilation and wood-fired heating appliances. The supported track, which applies to major renovations, now excludes homes that keep gas heating after the works. Finally, the decree postpones from 1 January 2027 to 1 January 2028 the date from which access to the single-measure track was to require an energy performance diagnosis, homes rated F and G keeping access to that track in the meantime.
Practical scope. For projects being put together, the date the application is filed becomes decisive. Before committing to any works, it should be checked that the chosen package remains eligible for the chosen track and that the heating system kept after the works does not bar the grant, otherwise the financing plan for a major renovation may be called into question mid-way.
Energy savings certificates
The Journal officiel of 6 September 2026 published an order of 4 September 2026 on replacing fuel-burning equipment already counted under the energy savings certificates scheme (JORF No. 0208 of 6 September 2026). It deals with how two successive operations on the same equipment fit together and how the second replacement is counted, a recurring question in boiler replacement programmes. The Journal officiel of 4 September also published an order of 1 September 2026 creating standardised operation sheet IND-UT-141, with its control framework and associated bonus, whose scope is limited to industrial utilities.
Social housing
Decree No. 2026-840 of 2 September 2026 allocating the remaining liquidation surplus of the public housing office of Champigny-sur-Marne (JORF No. 0206 of 4 September 2026) settles the fate of the sums left after the office was dissolved. Its scope is individual, but it illustrates how Article L. 421-7-1 of the Construction and Housing Code works, a mechanism set to come into play as social housing bodies continue to merge.
II. Case law
The third civil chamber held its first post-summer hearing on 3 September 2026 and handed down, on that day alone, six judgments published in the Bulletin, several of which bear directly on real estate and construction practice. On the administrative side, the period was mainly marked by commentary on a decision from last April on commercial planning.
Commercial planning: permit granted before the time limit for referral to the CNAC expired
CE, 8 April 2026, Société générale de distribution en Guyane, No. 497528. Commented on this week, the decision clarifies the fate of a building permit doubling as a commercial operating authorisation, granted on the favourable opinion of the departmental commercial planning commission while the time limit for referral to, or self-referral by, the National Commission (CNAC) had not yet expired. The Conseil d’État first holds that the permit is not unlawful merely because it was granted early. It then holds that the National Commission’s subsequent unfavourable opinion, which replaces the departmental commission’s favourable one, makes the permit unlawful from the moment it was issued. Finally, it draws a procedural consequence: the permit retains its nature as a commercial operating authorisation, so the persons listed in Article L. 752-17 of the Commercial Code may challenge it before the territorially competent administrative court of appeal, ruling at first and last instance, under the conditions of Article L. 600-1-4 of the Planning Code.
Practical scope. Municipalities are strongly advised not to grant the permit before the time limits for referral to the CNAC have expired. For the applicant, obtaining the permit quickly is false comfort: a subsequent unfavourable national opinion makes it retroactively unlawful, and the expiry of the time limits for challenging the permit does not prevent this.
Commercial lease: automatic rent increase clause deemed unwritten
Cass. 3e civ., 3 September 2026, No. 25-14.904, published in the Bulletin (quashed). A commercial lease clause providing, as an ancillary matter, that the rent will increase periodically, automatically and by a fixed amount, with no ceiling and no time limit, does not set the initial price of the lease: it organises its automatic upward-only review. As it defeats the mandatory rules on rent review, it must be deemed unwritten.
Practical scope. The line between a clause setting the price, which is valid, and one organising its review, which is subject to the mandatory rules of Articles L. 145-37 et seq. of the Commercial Code, turns on the absence of a ceiling and an end date. Leases with open-ended step increases deserve an audit, since the « deemed unwritten » sanction is not subject to limitation.
Subcontracting: additional works and failure to require a guarantee
Cass. 3e civ., 3 September 2026, No. 24-15.620, published in the Bulletin (quashed). A court of appeal fails to give a legal basis to its decision under Article 14-1 of Law No. 75-1334 of 31 December 1975 where, having found that the project owner breached its obligation to give the main contractor formal notice to provide a guarantee to the approved subcontractor, it dismisses the subcontractor’s claim for additional works on the ground that the owner was unaware of its involvement in those works, without examining whether they had been entrusted to it for the performance of the main contract.
Practical scope. The test of connection to the main contract prevails over the owner’s actual knowledge. Once the subcontractor has been approved and the additional works form part of the performance of the contract, the formal notice obligation also covers those works, and failure to comply engages the owner’s liability.
Subdivision: the specifications cannot be relied on against the municipality taking over common areas
Cass. 3e civ., 3 September 2026, No. 24-16.968, published in the Bulletin (dismissed). A municipality to which all the roads and common areas of a subdivision are transferred under its specifications is not a co-owner of the subdivision: the stipulations of the specifications cannot therefore be relied on against it. A court of appeal does not breach the law when, having found that a green space transferred to the municipality in accordance with the specifications had been incorporated into the public domain and then declassified after it had actually ceased to be used, without that declassification being challenged, it holds that the municipality’s sale of property in its private domain could not be called into question by the lot owners.
Practical scope. Transferring all common parts takes the municipality outside the contractual circle of the subdivision. Lot owners wishing to preserve the purpose of a green space must therefore act on administrative grounds, by challenging the declassification decision within the time limit for an action for annulment, and not on the basis of the specifications.
Electricity meters in buildings: public works and administrative jurisdiction
Cass. 3e civ., 3 September 2026, No. 25-12.638, published in the Bulletin (quashed). An electricity meter, which forms part of the individual connection into which it is incorporated and whose function is to record consumption, is, like the connection itself, an appurtenance of the electricity network and as such constitutes public works, regardless of whether it can be separated from the connection or removed without affecting the integrity of the installation. A claim seeking the removal or relocation of a set of meters installed under a roll-out policy provided for by law, absent any unlawful act of force, seeks to change the organisation of the network within the building and falls within the jurisdiction of the administrative courts.
Practical scope. Co-ownership disputes over smart meters fall outside the jurisdiction of the ordinary courts where they seek the removal or relocation of the equipment. Suing the network operator before the judicial court exposes the claimant to an objection of lack of jurisdiction.
Expropriation and liability insurance: two procedural points
Cass. 3e civ., 3 September 2026, No. 24-18.812, published in the Bulletin (dismissed). Although parties represented by a lawyer before the court of appeal ruling on expropriation may, since 21 May 2020, make the notifications and filings under Article R. 311-26 of the Expropriation Code electronically, they must still, on pain of their appeal lapsing, file or send to the registry within three months a paper copy of their submissions for the government commissioner, who has no access to the lawyers’ private virtual network.
Cass. 3e civ., 3 September 2026, No. 24-18.678, published in the Bulletin (dismissed). A victim who appeals a judgment ordering the insured and its insurer to compensate it, and then withdraws the appeal against the insured alone, may have the insurer rely on the limits of the awards that have become final as a result of that withdrawal, which amounts to acceptance of the judgment as between the insured and the victim.
Practical scope. In expropriation matters, electronic filing does not dispense with the paper copy for the government commissioner, failing which the appeal lapses. In construction insurance, a partial withdrawal of the appeal against the insured fixes the ceiling the insurer may rely on: the appeal strategy must be decided with this effect in mind.
III. Other points to watch
Residential leases: new standard contracts from 1 October 2026
Decree No. 2026-596 of 6 July 2026, amending Decree No. 2015-587 of 29 May 2015 on standard lease contracts for housing let as a main residence and Book VIII of the Construction and Housing Code, drew several commentaries during the week. Its Article 1, which recasts Annexes 1 and 2 of the 2015 decree, comes into force on 1 October 2026 and applies to contracts concluded or renewed from that date; its Article 2, on handling rent arrears and social support arrangements, comes into force on 1 January 2027, with in particular a new Article R. 824-15 of the Construction and Housing Code. Lease templates and termination clause models must be updated before 1 October.
Financing: rates rise again after the summer
Barometers published by mortgage brokers at the start of the month put the average rates actually obtained at around 3.40% over twenty years and 3.50% over twenty-five years, the best applications staying close to 3.10%. After several months of stability, the rise that began in mid-August tracks the increase in the ten-year OAT yield. The meeting of the European Central Bank’s Governing Council on 10 September 2026 will be the next reference point. These figures come from private bodies and do not carry the weight of Banque de France statistics, but they affect whether loan conditions precedent can be met and call for particular attention to the validity period of offers and to how time limits are drafted in preliminary contracts.
To watch
The directorate for housing, planning and landscapes renewed its delegations of signature on 1 September 2026 (JORF No. 0205 of 3 September 2026), the usual sign that rule-making is resuming after the summer. The implementing texts still to be adopted under Law No. 2025-1129 of 26 November 2025 simplifying planning and housing law are expected in the coming weeks, following the decrees already published over the summer.
The firm advises on French real estate and construction law.
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