Team Advisory

flex office or assigned desks: which way of working should you choose?

Regulatory and economic framework: a structuring cost per workstation, with a regulatory trajectory imposing a 40% reduction in the energy consumption of commercial buildings

Deciding in favour of flex office without 8 weeks of sensor measurement means arbitrating 250 EUR/sqm/year on a hunch. The Tertiary Decree (ELAN law no. 2018-1021) imposes a 40% reduction in consumption by 2030: no real estate decision holds up without time-stamped occupancy data. On the floor plates audited by KYTOM since 2006, the average occupancy rate ranges between 45% on Tuesdays and 30% on Fridays. An assigned desk costs 9,000 to 12,000 EUR per year. A flex office calibrated at 0.75 generates 20 to 30% space savings, subject to compliance with the Labour Code (R4222-1) and the Tertiary Decree. According to INSEE (Employment Survey 2023, March 2024), 22% of French employees work remotely at least one day per week: the theoretical occupancy projection is now structurally wrong.

The Tertiary Decree (ELAN law no. 2018-1021, articles L174-1 and R174-22 of the Construction Code) imposes a 40% reduction in energy consumption by 2030 for buildings larger than 1,000 sqm, with an annual declaration on ADEME’s OPERAT platform. This constraint pushes real estate departments to scrutinise every underused square metre.

For the CFO and Asset Manager: three orders of magnitude structure the cash-flow decision.

Full cost of an assigned desk: 9,000 to 12,000 EUR per year, rent + charges + energy + services + IT.
Occupancy rate measured by IoT sensors: 45 to 55% on a Tuesday, below 30% on Friday.
Potential savings of a flex office at a 0.7 ratio: 20 to 30% of leased space avoided.

On a 1,500 sqm floor plate at 550 EUR/sqm/year IRC, that is 165,000 to 247,000 EUR of rent avoided per year, i.e. 8 to 12 times the furniture CAPEX amortised over 9 years (median amortisation period used, consistent with CNC art. 942-21). This decision falls under structural OPEX, not the HR decision.

The Labour Code governs these choices via article R4222-1 et seq. on ventilation, article R4223-1 on lighting, and article R4213-5 on noise. Standard NF EN 12464-1:2021 sets 500 lux on the work surface. Standard NF S 31-080:2006 categorises acoustic performance levels in open-plan offices. The right working model depends on the job, the actual attendance rate and managerial maturity, never on a generic benchmark.

At what floor plate size does flex office become profitable?

Above 800 sqm or 60 employees, with a measured attendance rate below 70%. Below that, IoT sensor instrumentation and the three-month workshop cost more than the space savings generated (ROI > 5 years). KYTOM then switches to a short 3-week diagnosis (badge data only) without a prototype.

Which flex ratio to adopt: 0.7 or 0.8?

The ratio is calibrated over 8 weeks of IoT sensor measurements, never on a generic benchmark.