How Do You Calculate Office Cleaning Time?

A prospect calls us with a figure already in mind. He has 1,200 m² of offices, he has read somewhere that an agent cleans 600 m² per hour, and he concludes that he needs a two-hour visit. After the site survey, the real requirement is close to five hours. His calculation was not wrong: it was incomplete. He had left out half the work.

Calculating office cleaning time is not a matter of dividing a surface area by a productivity rate. It is a breakdown zone by zone, task by task, to which you add time that nobody counts and that nonetheless weighs heavily. Here is the method we apply on our sites, the rates we actually use, and a complete calculation worked through from start to finish.

Why calculating by surface area alone does not work

Return to the prospect's case. His 1,200 m² contained ten washroom blocks, three kitchens, eighteen meeting rooms, interior glazing and several floors served by a single lift. None of this appears in a total surface figure. All of it consumes time, and some of it consumes a great deal.

The underlying problem is this: two 1,000 m² floors can differ by two hours. One is a clear open-plan space, the other lines up fifty partitioned offices, four kitchenettes and twelve washrooms. Same surface, same frequency, working times with nothing in common.

Surface area is often the least interesting figure in a cleaning quote. We would rather know the number of washroom blocks than the total floor area to within ten square metres.

That statement would irritate part of the industry, and deliberately so. Calculating by surface area remains useful — as a starting point, to get a rough order of magnitude. Claiming it is enough to price a contract is an illusion of precision. What consumes time is not square metres. It is objects, people, equipment, access constraints and the standard expected.

Real productivity rates by space type

A square metre of washroom has nothing in common with a square metre of open plan. These are the ranges we use to price work, for routine service — not for restoration work.

The 5-step method

Everything starts with a site survey. Pricing over the phone amounts to guessing.

Step 1 — Record the composition, not just the surface

On site we record surfaces, but above all what makes them up: number of offices, workstations, washroom blocks, water points, kitchens, meeting rooms, staircases, interior glazing, floor types. It is this composition that drives the time, not the total floor area.

Step 2 — Break the work into elementary tasks

We break the site into roughly ten distinct tasks: dusting worktops, vacuuming, washing floors, sanitising washrooms, restocking consumables, handling and removing waste, wiping contact points. Each task has its own rhythm and its own frequency — not all of them happen on every visit.

Step 3 — Apply the rate zone by zone

Each zone receives its own rate, taken from the table above and corrected by our history on comparable sites. The sum of these times constitutes the productive time.

Step 4 — Add the non-productive time

This is the most systematically forgotten item, and it is the subject of the next section. It is not a comfort margin: it is time genuinely spent on site during which nothing is being cleaned.

Step 5 — Build in a contingency margin

Five to eight per cent, depending on the complexity of the site. This margin absorbs daily reality: a lift out of service, a room still occupied at the end of the day, an unexpected spill to deal with. A quote with no contingency margin is a quote that will be exceeded.

Non-productive time: the 15 to 40 minutes nobody counts

In a typical Paris building, the agent goes through the same sequence every time: collecting the badge, signing in at the security desk, waiting for the service lift, reaching the storage room, preparing and loading the trolley, then at the end of the shift putting equipment away, taking waste to the designated area and returning the trolley.

The total usually falls between 15 and 30 minutes per visit. In highly secured buildings — head offices, sites under Vigipirate protocol, buildings with multiple controlled access points — it easily exceeds 40 minutes.

That variability is the key point. Two buildings identical on paper can differ by more than twenty minutes purely because of access procedures. Across five weekly visits, twenty minutes amounts to nearly seven hours per month. At a standard rate, that is over one hundred and fifty euros a month on a single site.

How frequency affects time per visit

The higher the frequency, the faster each visit. An office serviced five times a week requires 20 to 35% less time per visit than the same office cleaned once a week. Soiling has no time to settle: less accumulated dust, fewer marks, less scrubbing needed.

Beware the shortcut: the sum of five visits still far exceeds a single weekly visit. What falls is the unit time, not the budget. Increasing frequency improves the perceived result and the effective hourly cost, never the overall invoice.

There is a lower threshold. Below one visit per week on offices occupied daily, you gradually leave routine service behind. Each visit becomes a mini restoration job, with rates that collapse and a result that still falls short of expectations. It is a poor economic calculation dressed up as a saving.

A fully worked calculation on 1,200 m²

Take the prospect's site from the introduction: 1,200 m² across several floors, ten washroom blocks, three kitchens, eighteen meeting rooms. Here is the calculation worked through zone by zone.

To this productive time we add 25 minutes of non-productive time — controlled-access building, several floors, distant waste room — giving 4 h 43. A 5% contingency margin brings the total to approximately 5 hours.

The prospect's initial calculation gave two hours. The real requirement is two and a half times higher. The gap does not come from a badly chosen rate: it comes from the fact that 100 m² of washrooms and kitchens alone account for more than one hour thirteen, close to 30% of productive time for 8% of the surface.

Planned time versus actual time: a real case

A commercial building of roughly 2,000 m². On paper, a straightforward brief: two floors, conventional offices, a few meeting rooms. We had allowed 4 h 30 per visit. From the first week, the team was running at 5 h 45.

Three elements had been underestimated: an unusual quantity of interior glazing, desks heavily loaded with personal effects which considerably slowed dusting, and a complicated waste route with several storage rooms far apart from one another.

The easy reaction would have been to conclude that the team was working badly. Instead we ran a full timed study, zone by zone, then presented the findings to the client with two options: increase the visit duration, or reduce the scope of the service. He chose to raise the budget slightly in order to keep the quality level. The contract is still running.

We measure actual time systematically: agent clock-ins, attendance sheets, on-site inspections, team leader feedback. Actual times never match planned times exactly. On a settled contract, a variance of 5 to 10% is normal. When starting a new site, a variance of 15 to 25% is common over the first few weeks while the organisation beds in.

How to check whether a cleaning quote holds up

Six questions to ask. If your provider cannot answer the first four, the quote was not built — it was estimated.

1. How many hours per visit? A monthly flat fee with no associated hour volume cannot be compared. That is often the intention.
2. Which rate was applied, by zone? A single answer for the whole building signals a calculation based on total surface area.
3. Is access time included? Fifteen to forty minutes per visit depending on the building. Included or not, it changes the comparison.
4. How many washroom blocks and water points were counted? If they did not count them, they did not survey the site.
5. What falls outside routine service? Exterior glazing, floor restoration, carpet shampooing: these are priced separately.
6. What happens if actual time exceeds planned time? The answer to that question tells you more about a provider than its price.

Summary table: the figures to remember