An energy retrofit building envelope project on a tertiary or institutional asset simultaneously mobilises envelope, HVAC, photovoltaic, BMS and sometimes interior finishes. On high-end heritage assets, it adds architectural, patrimonial and normative constraints. The complexity far exceeds the bandwidth of commodity "subsidy-gateway" retrofit actors or of multi-trade installers without integrated engineering.
Our service addresses owners who need to treat a tertiary, institutional or high-end heritage asset (primarily France: décret tertiaire, EPC, CREM. Switzerland: MoPEC, CECB+, Minergie retrofit. Plus EU EPBD, UK MEES, DE GEG). We operate as Lead Designer one-stop-shop or Orchestrating Owner's Engineer. Strict scope: envelope and inter-trade coordination, we do not install HVAC, photovoltaic or BMS ourselves.
Coordinate the deep retrofit of a complex asset, carrying technical, economic and contractual coherence, without becoming an executor of all lots.
Our role is to coordinate, arbitrate, pilot. Not to install HVAC, photovoltaics or BMS directly. This posture has multiple virtues: it preserves our neutrality on technical choices (no interest in pushing this heat-pump manufacturer, this BMS editor, this BIPV installer); it preserves our arbitration capacity between specialist partners, which grounds the counsel's value on these projects; it confines industrial risks to actors whose trade it is.
The energy-retrofit market, particularly in France, is polluted by commodity actors with opaque commercial interests (subsidy-gateway networks, turnkey-system resellers, poorly-trained high-volume installers). These actors may have their place on modest residential retrofits; they are unsuited to high-end tertiary, institutional or heritage assets where technical, contractual and aesthetic requirements demand integrated engineering and structured governance. Our positioning is the opposite: high-end, integrated engineering, trusted third party, human size, discretion. We serve institutional owners and family offices seeking a counterpart who speaks their language.
Four typologies structure our intervention on envelope deep retrofit.
Offices, headquarters, corporate campuses, tertiary retail centres. 5,000 to 50,000 m².
Offices, headquarters, corporate campuses, tertiary retail centres. Typical size: 5,000 to 50,000 m², sometimes larger on headquarters or institutional campuses. Central challenge: aligning with regulatory trajectories (décret tertiaire in France, MoPEC in Switzerland, MEES in UK) while preserving or enhancing leasing attractiveness and heritage value.
Administrations, universities, hospitals, public and para-public establishments.
Multiple challenges: public budget constraint, multi-actor governance (owner, investment committee, supervising authority), reporting and audit requirements, political calendars. The retrofit must fit voted budget envelopes and respect public-procurement rules.
UHNWI residences, prestige hotels, historical buildings transformed into high-end assets.
Absolute discretion, elevated quality requirements, signature-architect coordination, compliance with heritage constraints (listed-building authorities). The retrofit must preserve or enhance the architectural signature while delivering targeted energy performance.
−40 % by 2030, −50 % by 2040, −60 % by 2050 on tertiary stock above 1,000 m². UK MEES tightening EPC C/B.
Owners subject to consumption-reduction obligations on their tertiary portfolio. For these owners, retrofit is no longer optional: it is a regulatory constraint with firm deadlines and sanctions. Our mandates help them sequence and phase retrofits to hold trajectories without value destruction. In the UK, MEES progressively pushes EPC C and B as commercial-leasing minimum.
Regulatory contexts differ sharply across Europe. Each jurisdiction has its logic, contractual tools and financing instruments. Trajectories converge (decarbonisation of the built stock), but calendars and levers differ. Correct works sequencing depends strongly on the applicable framework.
The revised EPBD (Energy Performance of Buildings Directive) sets trajectories for Minimum Energy Performance Standards (MEPS) on non-residential and residential stock, with Member State transposition deadlines. CSRD and SFDR reporting requirements indirectly push institutional investors toward retrofit programmes on underperforming assets to prevent stranded-asset exposure. The EU Taxonomy frames asset-level alignment requirements.
Obligation for tertiary buildings above 1,000 m² to reduce energy consumption by −40 % by 2030, −50 % by 2040, −60 % by 2050 against a reference year. Sanctions: "name and shame", administrative penalties, leasing-attractiveness loss. OPERAT platform (ADEME) centralises declarations. Complementary instruments: Energy Performance Contract (CPE), Design-Build-Operate-Maintain (CREM), labels (BBC Rénovation, HPE Rénovation, BBCA Rénovation).
MoPEC (Modèles de prescriptions énergétiques des cantons, editions 2014 and 2025 in transposition) sets cantonal energy requirements on retrofits. Federal-cantonal Programme Bâtiments subsidises envelope insulation, heating-system replacement, solar installations, CECB+. CECB / CECB+ Cantonal Building Energy Certificate is a gateway to subsidies and informs the patrimonial business case. Labels: Minergie, Minergie-P, Minergie-P-ECO.
MEES (Minimum Energy Efficiency Standards) progressively tightens EPC rating requirements on commercial leasing, with 2030 targets pushing C and B ratings to become the minimum. Non-compliant assets become unleasable: a direct stranded-asset risk.
GEG (Gebäudeenergiegesetz) sets energy requirements on new-build and retrofit, with evolving trajectories on heating-system technology and building-envelope performance. Our practice navigates these frameworks simultaneously: many of our owners hold pan-European portfolios where the retrofit strategy must be coherent across jurisdictions.
Our scope precisely defines what we carry and what we leave to specialist partners. This clarity avoids the grey zones that destroy value on poorly-framed retrofits.
Diagnostic, strategy, technical piloting, coordination, business case, governance.
HVAC, PV/BIPV execution, BMS, interior insulation: carried by specialist engineers and installers.
This division of labour is a quality guarantee: each lot is carried by a specialist dedicating its practice to it, under our coherent orchestration. It also avoids liability grey zones in case of subsequent defect.
Sizing, technology choice (heat pumps, heat recovery, double-flow ventilation), installation, commissioning. Carried by a specialist HVAC engineer or installer. We coordinate the envelope ↔ HVAC interface without carrying HVAC engineering itself.
Production study, module selection, electrical installation, grid connection. Carried by a specialist PV engineer or installer. For architectural BIPV integration (modules embedded in the skin), we pilot via our BIPV specialty sheet, but installation remains with a partner.
Building-management systems, sensors, automation, operation dashboards. Carried by a specialist BMS engineer or editor. We define envelope sensor requirements and interfaces, without carrying BMS engineering.
Internal wall insulation, partitions (beyond exterior envelope). Carried by a specialist second-fix engineer or contractor. We treat the exterior envelope; interior insulation is a complementary lot when required.
The choice reflects the owner's profile: internal structure, maturity on deep retrofit, governance preference.
Complete Lead Designer mission from initial diagnostic to final handover; owner's single counterpart.
Advisory: validate strategic choices, arbitrate between contractors, control technical coherence.
Shili & Partners carries the complete Lead Designer mission for the owner, from initial diagnostic to final handover. We pilot the envelope directly, coordinate non-envelope lots via specialist engineers and installers, and serve as the owner's single counterpart throughout the project.
This mode suits owners new to deep retrofit: single-asset family offices, small institutional owners without a structured property department, corporate executives retrofitting their headquarters. They seek a single counterpart carrying complexity on their behalf. Our liability is broader (global project coordination, budget and global planning piloting, owner reporting). It demands significant bandwidth from our atelier over the project's duration. We take this mandate only on projects whose complexity and patrimonial value justify it.
Shili & Partners accompanies the owner in advisory. We validate strategic choices, arbitrate between contractors, control technical coherence, while leaving the Lead Designer mandate direct or with another actor (mandating architect, classic multi-discipline design team). Our role is orchestrator, not Lead Designer proxy.
This mode suits structured institutional owners (real-estate funds, developers, public bodies, industrial groups) who have an internal property team able to manage a classic design team, but who want an independent orchestration layer and a specialist envelope expertise they lack in-house. The Orchestrating OE position preserves the neutrality required on sensitive projects: notably when several signature architects are consulted, when several D&B consortiums bid, or when the project crosses political decisions (public projects, institutional projects). Our arbitration remains audible precisely because it has no commercial engagement with the contractors.
IMG.056aDeep energy retrofit does not read as a cost to absorb. It reads as a patrimonial value driver. A properly retrofitted asset gains in leasing attractiveness, rent levels, occupancy duration, resale value. Four terms costed systematically over the owner's holding horizon (typically 7 to 15 years).
Value gap between retrofitted and non-retrofitted asset, combining leasing-attractiveness uplift (higher rents, longer occupancy, label premium) and avoided discount on non-compliant assets at resale time. Costed on market benchmarks per asset typology and geography.
Measurable OPEX savings over the horizon (reduction of heating, cooling, ventilation, lighting consumption). Modelling with stabilised climatic hypotheses and energy-cost scenarios. Integration of avoided charges (carbon taxes, energy-efficiency certificates) per jurisdiction.
Programme Bâtiments (Switzerland, by canton), MaPrimeRénov' Copropriétés (France), regional or cantonal aids, CEE, label bonuses (BBCA, Minergie-P-ECO). Case-by-case costing per asset, eligible measures and applicable canton/programme. On profiles that fully mobilise them, these subsidies weigh significantly on the final ROI.
Asset positioning against expected regulatory tightening (DEET trajectory, MoPEC 2025 milestones and beyond, evolving EU Taxonomy, UK MEES targets). Assessment of the cost and delay of a subsequent compliance retrofit vs integration into the current deep retrofit. The four terms are synthesised in a scenario matrix (minimal retrofit, optimal retrofit, ambitious retrofit) with ROI calculated for each.
Four guardrails define what we refuse on this service, to protect counsel quality and atelier sustainability.
Decennial carried by executing contractors; we carry complementary design-team liability.
Decennial warranty is carried by the contractors executing works (facade contractor, GC, HVAC installer, PV installer, BMS installer) with their construction liability insurance. Our atelier as Lead Designer or Owner's Engineer carries design-team professional liability, complementary but distinct. We refuse arrangements where our atelier would become the primary bearer of a decennial warranty extended beyond our counsel mission.
Selection, piloting, control; not execution. Neutrality protection.
These lots are carried by specialist partners. We may select them, pilot them, control their execution, but not execute ourselves. This separation protects neutrality: we have no commercial interest in pushing this solution, this manufacturer, this installer.
Market polluted by subsidy-gateway networks at volume; we bid elsewhere.
The energy-retrofit market, particularly in France, includes numerous "subsidy-gateway network" actors operating at volume, whose economic model is incompatible with our positioning (integrated engineering, institutional heritage, high-end). We do not bid on the same projects and we refuse mandates that would place us in this posture.
Performance commitment requires solidary industrial partner; S&P role = OE structuring.
An Energy Performance Contract with measurable-savings commitment cannot rest on counsel alone, it requires an industrial partner solidarily carrying the performance risk (installer, ESCO). Our role in an EPC is Owner's Engineer on structuring and control, not co-contractor of performance.
The deep energy retrofit service articulates with four other atelier services.
Technical pillar whose complete set of services is mobilised in deep retrofit (diagnostic, design integrity even on retrofit, project economics, carbon, DFMA, procurement, site supervision). Retrofit is a particular form of Envelope Engineering application.
Format 1 of Conception-Réalisation (international mega-projects). Our deep energy retrofit is Format 2, same orchestration backbone, different markets and contractual frames. Both services share the practice muscle. See Design-Build Lead.
Energy retrofit is a central application case of the carbon strategy. The tools (parametric LCA, low-carbon sourcing, decarbonation trajectories) are mobilised in our deep retrofit mandates. See Carbon Strategy and Decarbonisation.
Contractual form under which we operate when the Orchestrating Owner's Engineer mode is chosen, with all the neutrality rules of the OE positioning. See Owner's Engineer.
The envelope energy retrofit mobilises several atelier disciplines. Five entry points to explore.
Overview of the complete engineering discipline applied to existing tertiary assets.
Upstream reading that structures the retrofit strategy.
Consortium lead posture for ambitious heavy rehabilitation retrofits.
Site supervision specific to the retrofit of an existing asset.
Handling of disputes on existing contractual positions (warranty recovery, DOE gaps).