A commercial unit falls under two separate obligations, triggered by different criteria. French decree no. 2019-771 of 23 July 2019, known as the tertiary decree, applies as soon as the activity occupies a cumulative floor area of at least 1,000 m² on one site, with annual consumption reporting on the OPERAT platform and a reduction trajectory of 40% by 2030, 50% by 2040 and 60% by 2050. The building automation decree ignores floor area and triggers on the rated useful output of the heating, cooling and ventilation systems: a 300 m² unit with more than 70 kW installed is caught. Knowing which of the two applies sets the scope of works before any question of insulation or lighting arises.
Identifying which obligations apply to the unit
Two decrees, two triggers
Confusing the two texts either reassures an operator wrongly or prices an obligation that does not exist. The table below separates their scopes.
| Tertiary decree | Building automation decree | |
|---|---|---|
| Trigger | Cumulative tertiary floor area of at least 1,000 m² on one site | Rated useful output of heating, cooling and ventilation systems |
| Thresholds | 1,000 m² | 290 kW, then 70 kW |
| Main obligation | Annual consumption reporting and a reduction trajectory | Installation of a building automation and control system |
| Target | Minus 40% by 2030, minus 50% by 2040, minus 60% by 2050, or an absolute target | Control, monitoring, analysis and detection of consumption drift |
| 300 m² unit with 100 kW installed | Not caught | Caught |
A restaurant, a mid-sized food retail unit or any unit with heavy refrigeration reaches the capacity threshold long before the floor area threshold. That is the configuration most often missed during a survey.
The automation deadlines in 2026
For existing buildings, the obligation has applied since 1 January 2025 to installations above 290 kW. For the 70 to 290 kW band, the deadline originally set at 1 January 2027 has been postponed to 1 January 2030 by decree no. 2025-1343 of 26 December 2025. For new buildings, it has run since 21 July 2021 above 290 kW and since 8 April 2024 above 70 kW. An exemption remains possible where a study shows a payback period longer than ten years, and that study has to be produced, not merely asserted.
What the postponement changes in your pricing
A three-year postponement is not an exemption, and it creates a trap: an operator who replaces a generator in 2027 without providing the control interface will have to reopen the installation before 2030. On any work touching generation or distribution, price the compatibility with an automation system now, even if the client is not ordering it. The scope and reporting obligations are set out in our article on the tertiary decree.
Surveying before proposing works
Establishing the real consumption split
A commercial unit is not surveyed like a dwelling. The dominant end uses vary fivefold with the activity, and intuition often misleads: a shop consumes mostly in lighting and heating, a restaurant in extraction and refrigeration, offices in heating and IT. Start with the bills and with hourly readings, not with the envelope. The metering data available and how to use it are covered in our article on smart meters. Those readings come together faster when the actual metered consumption is retrieved from the network operators with the client's consent.
Sub-metering the heavy end uses
Temporary sub-metering over a few weeks beats an estimate. Target commercial refrigeration, cooking and extraction, sales-floor lighting and the sign. Those four end uses carry most of the savings potential in retail, and they are also the ones that make a credible funding application. Without measurement before the works, no gain can be demonstrated afterwards.
Surveying the envelope where it is genuinely weak
In a commercial unit, losses concentrate at the facade and at the trading openings. Poorly sealed shopfronts, automatic doors left open, no lobby, slab to facade junctions, shutter boxes, service penetrations. A thermal imaging survey during trading hours, with the plant running, gives the real map of the leaks, and in particular shows what customer footfall costs in uncontrolled fresh air. Treating the junctions is developed in our article on thermal bridges.
Prioritising the works in a tertiary setting
Control before hardware
In a commercial unit, the first saving rarely comes from the machine. It comes from schedules, setpoints and zoning. Plant heating and cooling at the same time, extraction running at full rate outside trading hours, a sign lit overnight: those three faults are corrected without heavy investment and show up in a few weeks. It is also the logic the automation decree formalises, by requiring a system able to detect drift.
Envelope and roof, where the square metre counts
In a tertiary setting, the insulation that pays back fastest is the one that does not eat into sales area: roof, ceiling, service voids. Perimeter linings, by contrast, cost trading square metres, which changes the economics entirely compared with a dwelling. Express that cost in area lost and turnover per square metre: it is the only language in which an operator can decide.
Lighting and commercial refrigeration
The combination of LED, presence detection and daylight dimming remains the most profitable measure on a sales floor, provided it does not degrade the colour rendering and illuminance the activity requires. On refrigeration, closing the cabinets, night blinds and heat recovery from the refrigeration plant often deliver more than replacing the plant itself, and they require no trading interruption.
Running the job in an occupied unit
Zone phasing and hold points
The principle is simple and it lives in writing: one isolated zone, secured customer circulation, a signed hold point, then the next zone. Noisy work or anything cutting a service goes outside opening hours. The shared programme covers deliveries, waste removal and stockroom access, points where the operator has constraints you cannot see from the site.
Safety and compliance in public-access premises
Check from day one the requirements specific to public-access premises: escape routes and exits kept clear, temporary signage, first-intervention equipment, dust protection. Formalise a prevention plan as soon as several contractors work alongside each other. The accessible route has to stay usable throughout the works, including during strip-out.
What the quote has to carry
A quote for a commercial unit is distinguished by three lines: the working hours window, the conditions for keeping the unit trading, and a condition survey of the existing installations. Without them, every operating constraint becomes a claim. The mandatory particulars common to any works quote are set out in our article on quote requirements. Those three lines stay in the document when material, labour and accessories come through from the works plan with the required particulars already written.
Proving the result
Documented commissioning
Real performance is decided at the settings. Measured flow rates, balancing, setpoints, schedules, control parameters: all of it goes into a commissioning report, with the values recorded rather than the values intended. On a controlled installation, add a copy of the time schedules as configured and the name of the trained person on the operator's side.
Consumption monitoring and a metering plan
A metering plan established before the works and read after them is the only way to demonstrate a gain. Four to eight weeks of monitoring after commissioning allows setting drift to be corrected, and that drift often exceeds the difference between two pieces of equipment. The comparison method and its pitfalls are detailed in our article on monitoring consumption after a retrofit.
The file the operator lives with
Hand over a complete as-built file, the manuals, the control parameters, the metering plan and the reference-year reading where the unit is subject to the tertiary decree. That last item is the one the operator cannot reconstruct later, and the one on which their whole reporting trajectory depends.
