Calculating the office space you need: the Kytom method, square-metre-per-employee ratios, flex office sizing and lease arbitration for real estate teams.
"We have 1200 m2 - is that too much, just right, or not enough"
On a Paris lease at 650 euros/m2/year excl. tax and charges, 200 m2 of surplus space represents 130,000 euros per year, or nearly 400,000 euros over the firm term. Conversely, undersizing forces an early relocation whose average cost exceeds 1500 euros per workstation.
A ratio below 8 m2 per workstation degrades concentration and acoustics: a measurable rise in stress is observed beyond 0.55 dB(A) of excess ambient noise. Field feedback confirms that 52% of employees cite the lack of confidential spaces as their leading daily irritant.
Regulations set a minimum air volume per occupant and recommend 10 m2 per workstation in a shared office, 15 m2 in a shared individual office. In parallel, an energy reduction trajectory of 40% by 2030 applies to the tertiary sector, which penalises underused space.
Kytom combines three data sources to ensure reliable sizing: presence sensors calibrated over 4 to 6 weeks, manager interviews by department, and a 36-month HR projection. This triangulation, deployed across 1200+ projects, reveals an average gap of 22% between perceived space and actual usable space. On an average footprint of 850 m2 per project, we apply standardised occupancy ratios and recent sector benchmarks to frame a programme suited to the target presence rate. The final deliverable includes a flex scenario, a nominal scenario and a growth scenario, each costed in terms of fit-out cost and projected rent over seven years.
Installation of anonymised sensors for 4 to 6 weeks, acoustic and thermal audit, mapping of existing space typologies. Deliverable: a detailed occupancy report by floor, by day and by typology, with measured presence rate and gap against the sector's reference ratios.
Framing workshop with the project manager, HR department and real estate department to validate the presence policy, the workstation sharing ratio and meeting room needs. Deliverable: a functional programme costed in usable square metres per typology, validated by the executive committee.
Three compared master plans (reduced space, stable space, extended space), with simulation of fit-out cost, projected rent and energy performance. Deliverable: a decision matrix and dimensioned 2D plans, ready for arbitration by the real estate committee.
Works executed in an average of 12 weeks, then a new sensor campaign at three months to verify the match between delivered space and actual use. Deliverable: a post-occupancy report with corrective adjustments if the gap exceeds 10%.
"We thought we were 300 m2 short - the diagnosis showed the opposite: we had 18% of underused space. Resizing saved us 210,000 euros in annual rent."
The NF X35-102 standard recommends 10 usable m2 per workstation in a shared office and 15 m2 in a shared individual office. In flex office, the ratio drops to 6 to 8 m2 per employee present, with a sharing ratio of 0.7 workstation per person.
Anonymised presence sensors installed for a minimum of 4 to 6 weeks, cross-referenced with badge data. In hybrid mode, the average occupancy rate sits between 45% and 60%, compared with 70% before 2020.
Yes, over a 36-month horizon consistent with the firm term of the 3/6/9 lease. Kytom systematically models three HR scenarios (low, median, high) and applies a 10 to 15% margin on the programmed space.
Across 1200+ projects delivered, the average reduction reaches 20 to 30% of leased m2 when the presence policy is below 4 days per week. Beyond that, the gain fades and individual comfort must take priority.
The tertiary eco-energy decree requires a 40% reduction in consumption by 2030. Oversized space mechanically penalises the kWh/m2 ratio, which makes downward resizing consistent with the energy trajectory.
12 to 18 months before the firm term, to allow time for diagnosis (2 months), framing (1 month), lease negotiation (3 to 6 months) and works (12 weeks on average).