Occupancy sensors for offices are sold as the answer to how full the building is, and they are the input to it. A sensor under a desk, on a ceiling or at a door produces a count of people in a space over time; workplace occupancy is that count set against the desks and the area the space has, and the setting-against is arithmetic the sensor does not do. This guide is written from the facilities team's side of the wire: what occupancy sensing, workplace occupancy sensors, office sensors, workplace sensors and space utilization sensors actually produce, what the count has to be set against, and why the free worksheet on this site works the same figures from a clipboard count as from a ceiling full of hardware.
What the sensors produce: a count, by space, over time
Desk sensors say whether a position is occupied and for how long; room sensors count people in a room; door counters and badge readers count entries; wifi association counts approximate people on a floor. Each produces the same two numbers the workplace team needs, people in on an average day and people in on the busiest day, at a finer grain and without a person counting. That is the whole of what office sensors do, and it is a real improvement in how the input arrives and no change in what the input means.
What the count is set against
84 in on an average day against 140 desks is 60% utilization; 126 on the busiest day is 90%; 14 desks are spare; 12,000 square feet over 84 people is 142.9 square feet per person actually in; the attendance supports 7 desks per 10 people. Every one of those is the sensor's count divided by something the sensor does not know: the desks, the area, the headcount. The space utilization worksheet on this site does the dividing from the counts you enter, with no account, whether a sensor or a clipboard produced them.
Workplace occupancy kept week by week
The count is worth keeping because the trend is the evidence: a floor at 90% of desks on its busiest day in May and 110% in September has outgrown its ratio, and the lease conversation needs both months. Workplace occupancy sensors that keep the counts in the vendor's portal and export a monthly PDF have measured the floor and hidden the measurement; ask for the counts as a table by space and day. HardFM Pro keeps the weekly counts against the floor and exports them, for $24 a month for the whole team, and integrates with no hardware on purpose.
What this hub does not decide
Which sensor to buy, how it is installed and wired, what it costs, how it handles privacy and what the building code sets as maximum occupancy for egress are the hardware vendor's, the integrator's, counsel's and the fire authority's questions. HardFM publishes no sensor figure, no accuracy claim and no vendor's price; it takes the counts as inputs and works what they mean against the desks and the area.
Questions people ask about occupancy sensors for offices
What do occupancy sensors for offices actually measure?
A count of people in a space over time: desks occupied, people in a room, entries at a door, devices on the floor. The count becomes workplace occupancy only when it is set against the desks and the area, which is arithmetic the free space utilization worksheet does from the counts you enter.
Do I need space utilization sensors to measure utilization?
No. A badge count, a booking export or a manual count for a month produces the same two numbers, average and busiest-day attendance, and the worksheet works the same figures from them. Sensors change how the count arrives, not what it means.
Does HardFM integrate with office sensors?
No, on purpose. It takes the counts as inputs and keeps them week by week against the floor; the hardware, the wiring and the privacy questions belong to the vendor, the integrator and counsel.