The Greycoat CEO explains why the regulation creates structural advantages for refurbishment-focused developers—and what investors need to understand

When Nick Millican launched Greycoat Real Estate’s Paris office in March 2025, the timing was deliberate. Four months earlier, Paris had adopted the PLU Bioclimatique—the first bioclimatic urban planning document in France—and Millican saw exactly the regulatory environment his firm’s refurbishment strategy was built for.

“Paris offers the same fundamentals that made London fertile ground for Greycoat’s approach,” Nick Millican explains: “significant aging office stock, institutional capital flows, tightening environmental regulations, and strong tenant demand for high-quality, sustainable space.”

The 3,000-page PLU Bioclimatique, fully implemented from January 2025, makes that case concrete. Its core premise: renovation is “the new norm” and demolition is “the exception.” For investors, corporate occupiers, and developers navigating Paris real estate, understanding its implications is now essential.

The Regulation’s Architecture

The PLU Bioclimatique creates three categories of building intervention. “Rehabilitation” covers works affecting less than 15% of structural elements and carries the lightest compliance burden. “Heavy restructuring” applies to works affecting 15-50% of structure. “Reconstruction”—works affecting 50% or more—faces the most stringent requirements.

The critical detail for developers like Millican: works solely for energy performance improvement, health and safety upgrades, and thermal or acoustic insulation are explicitly excluded from “heavy restructuring.” This carve-out deliberately avoids penalising ecologically virtuous renovations—a structural advantage for refurbishment specialists.

The regulation sets sustainability requirements 5-15% more stringent than France’s national RE2020 standard on energy consumption, and 10-20% more ambitious on renewable energy integration. All projects exceeding 1,000 square meters require mandatory renewable energy installation. Air conditioning is permitted only as a last resort.

Why Nick Millican Sees Opportunity in the Carbon Mandates

The PLU Bioclimatique bans 100% concrete construction entirely. Buildings must use biosourced materials—wood, hemp, straw—or geosourced materials like stone and raw earth. Material reuse is mandatory: demolition and renovation materials must be considered for reuse rather than disposal.

This aligns with the philosophy Millican has championed throughout his career at Greycoat. “It’s extremely hard to demolish a building and then use what you’ve taken to then build a new building,” he notes. “It’s not really practical. So the more you can retain, the better the carbon footprint of what you’re doing.”

France’s RE2020 regulation—the first mandatory embodied carbon requirement globally—reinforces this logic. Thresholds tighten progressively: from 640-740 kg CO₂/m² in 2022 to 415 kg CO₂/m² by 2031. The UK’s equivalent Part Z remains under consultation, giving France a regulatory head start that Millican believes makes the brown-to-green strategy even more compelling in Paris than London.

Mixed-Use Requirements and Enforcement

The PLU Bioclimatique introduces mandatory mixed-use provisions. Operations exceeding 4,500 square meters of commercial space must include at least 10% housing. In predominantly office districts, major restructuring projects over 5,000 square meters must dedicate 10% to housing creation. Paris targets 40% public housing by 2035.

Enforcement is straightforward: non-compliant projects face permit denial. The “positive externalities” bonus system requires projects exceeding 150 square meters to demonstrate excellence across multiple sustainability criteria. Projects that fail cannot proceed.

This sits alongside the Décret Tertiaire, mandating 40% energy reduction by 2030, 50% by 2040, and 60% by 2050 for all commercial buildings over 1,000 square meters. Penalties include €7,500 fines per building plus public “name and shame” publication. Studies estimate 10-20% asset devaluation for non-compliant properties.

Reading the Market Through Millican’s Lens

Millican has long observed what he calls a “two-tier market” in London—prime sustainable buildings commanding rising rents while obsolete stock struggles. Paris now shows the same pattern. The CBD sits at 2-4.7% vacancy; La Défense registers 15-15.7%; northern suburbs reach 20%.

The opportunity is substantial: 57% of Paris office stock currently fails environmental standards. Progressive DPE rental bans are taking effect—G-rated properties from January 2025, F-rated from 2028, E-rated from 2034. La Défense alone holds 600,000 square meters of vacant space, much of it dated and non-compliant.

Analysts increasingly describe this as a “brown discount” rather than merely a missed green premium. BREEAM certification can increase Paris rents by up to 24.9%. Certified properties show 8% higher occupancy. Some 77% of employers report willingness to pay premiums for green-certified offices.

Nick Millican’s Paris Playbook

To execute in Paris, Millican recruited Arnaud Malbos—17 years at CDPQ/Ivanhoé Cambridge, with a track record including the DUO towers (100,000 sqm) and Cœur Défense (160,000 sqm). In September 2025, Semih Bayar Eren joined as Directeur Général, bringing legal expertise from Latham & Watkins and recognition in the Legal 500 GC Powerlist France 2024.

The strategy mirrors what Greycoat has proven in London, where projects like 20 Finsbury Dials—a 140,000 square foot refurbishment with Goldman Sachs Asset Management—target BREEAM Outstanding, EPC A, and WELL Platinum certifications. Millican sees Paris as validation that the model travels.

“It’s becoming increasingly hard to get permission to demolish buildings,” Millican observes of regulatory trends across European capitals. “You have to really justify why you’re doing it. It is not just a case that you make a bit more money.”

Paris has now written that principle into binding policy. For investors seeking to understand where the market is heading, Nick Millican’s bet on refurbishment offers a clear signal: the opportunity belongs to those who can transform what already exists.