Cleaning calculation explained: calculate the workload objectively

How much cleaning does a building really need? Anyone who answers that question with "we have always done it this way" usually ends up paying too much or too little. Cleaning calculation gives a factual, transparent answer to it.

What is cleaning calculation?

Cleaning calculation means systematically calculating a property's cleaning needs instead of estimating them. The basis is the actual areas, their use and recognised performance or standard values. The result is a justifiable effort, in hours, staff and costs.

The calculation always runs in the same direction: from the individual area via the time per cleaning and the annual hours through to the costs. Every item remains visible on its own. That is exactly what distinguishes a calculation from a flat rate: at the end you can say for every room how many minutes it costs and why.

Why estimating gets expensive

Blanket assumptions lead to two problems: if the effort is set too high, unnecessary costs arise. If it is set too low, quality and the building's substance suffer. Both come to light at the latest during a tender or a budget review. An objective calculation makes such discussions unnecessary, because every item can be documented.

The basics of the calculation

A clean cleaning calculation is essentially based on three variables:

• Area: the area to be cleaned per room and covering, recorded as precisely as possible.
• Performance value: how much area can be cleaned per hour for a given activity and floor covering.
• Interval: how often cleaning takes place, daily, weekly, seasonal.

The annual effort results from area, performance value and interval. In addition, special work such as deep and window cleaning as well as corrections for aggravating conditions are factored in.

The calculation step by step

The path from area to franc consists of five steps. They apply in the same way to every room, from the WC to the gym.

Step 1: determine the cleaning area per room

What counts is not the gross floor area but the area that actually has to be cleaned. Walls, structure, shafts and rooms that are not cleaned do not belong in it. How to establish this figure cleanly is shown in the article Area recording as the basis of the calculation. Each area is also assigned a Floor covering and a Room type.

Step 2: assign a performance value

The Performance value states how many square metres per hour can be cleaned using a particular method. It depends on the covering, the method and the room type. A machine-cleaned hall floor achieves a multiple of a sanitary room that is cleaned by hand and in several passes.

The values come from measured objects. In the calculation the matching value is assigned automatically as soon as covering and room type are recorded.

Step 3: calculate the time per cleaning

The area divided by the performance value gives the time for one cleaning pass. A long corridor with a smooth covering is therefore often cleaned faster than a much smaller sanitary room, because there every fitting, every partition and every corner is dealt with individually. The time per pass is the figure on which all further steps are based. It is determined for each area individually and not averaged over the whole building.

Step 4: apply interval and operating weeks

The time per cleaning is multiplied by the number of cleanings per week and by the Operating weeks . The biggest errors arise here: an administration building operates 52 weeks, a school building 39 school weeks, a gym somewhere in between depending on lettings. Anyone who calculates with 52 weeks everywhere overestimates school operations by around a third.

Step 5: convert annual hours into costs

The Annual hours times the hourly rate give the annual costs. For in-house staff, full costs are used, i.e. wages, social security contributions, holidays, absences, materials and machines. In Switzerland, around 45 francs is a usual internal rate; external service providers are mostly between 40 and 60 francs.

Difficulty factors: when the standard value is not enough

Standard values describe a normally equipped, normally used room. Where reality differs from this, the effort is corrected with surcharges. Five factors explain most deviations:

Indicative values for orientation, as at October 2026.

Worked example: administration building with 1,500 m2

A municipal administration building has 1,500 m2 of cleaning area and operates 52 weeks a year. The areas are spread over the basement, ground floor and two upper floors, across offices, meeting rooms, circulation areas, sanitary facilities and ancillary rooms. Every line is calculated individually.

The ratio stands out: the WC facilities are only a small part of the area but take up almost a quarter of the hours. It is precisely this shift that is lost when the whole building is calculated with a single average value.

The special cleaning line combines deep cleaning of the floors, window cleaning and cleaning after events. Experience shows that these items amount to around 10 percent of the Routine cleaning, i.e. around 98 hours here. The total effort therefore comes to around 1,088 hours per year.

From effort to statement

Once the effort is calculated, it can be translated into workloads and FTE percentages and compared against costs. This turns an area into a robust figure that can be used to plan, tender and compare, for all properties by the same rules.

In practice, three things come out of this: a budget that is justified item by item, a Specifications for the tender and a workload for each member of staff. Because all three come from the same calculation, they do not contradict each other. The steps from calculation to allocation and annual planning are shown by the modules Workloads and allocation and Route and annual planning.

Typical mistakes in the calculation

• Gross area instead of cleaning area: Walls, shafts, plant rooms and attics are not cleaned. What counts is the effective Cleaning area per room.
• One flat rate for everything: A single value for the whole building underestimates sanitary facilities and changing rooms and overestimates halls and corridors. The error only becomes apparent during execution.
• Forgetting operating weeks: 52 instead of 39 weeks produces an error of one third for a school building. Conversely, holiday operation is often left out altogether.
• Deep and window cleaning not budgeted: This work is rarely required but it costs money. If it is missing from the budget, it appears later as a supplementary credit. The differences are explained in the article Cleaning types compared.
• Empirical values instead of standard values: The existing workload only says what has been delivered so far, not whether it was appropriate. As a control figure it is useful, as a basis for calculation it is not.
• Difficulty factors counted twice: Anyone who chooses a low performance value and additionally applies a surcharge counts the same circumstance twice.

What the calculation actually delivers

For the budget: Every item is documented. If the area grows through an extension or an interval changes, the additional work can be shown in hours and francs instead of having to justify an increase that nobody can verify.

For the tender: The calculation produces a specification with areas, coverings and intervals. All providers then calculate on the same basis. This makes the offers genuinely comparable. The procedure is described in the article Tendering cleaning for the public sector.

For comparison: Two school buildings in the same municipality can only be compared sensibly once both have been calculated according to the same rules. Deviations then actually show differences in equipment or use, not differences in the estimating method.

The benefits at a glance

• Objective, justifiable budgets instead of gut feeling.
• A fair basis for tenders and offer comparisons.
• Full transparency towards committees, supervisory bodies and clients.
• Comparability across all properties.

How easyCAFM calculates

easyCAFM records every area with covering, room type and interval in the Objects and areas module and calculates the effort using standard values from more than 17,000 calculations by toolsuisse AG. The Cleaning calculation module then provides annual hours, FTE percentages and costs down to the individual area. Behind the software is toolsuisse AG, which has been producing workforce calculations in Switzerland since 2004; easyCAFM is developed by murmy GmbH in Rotkreuz. More on this on the page About us.

FAQ

How precisely does the area have to be recorded?

For a budget, room groups with a tolerance of around 10 percent are sufficient. For a tender or a binding workload definition, recording should be room by room, because every square metre feeds into the annual hours many times over through the intervals.

Where do the performance values come from?

Performance values come from systematic time studies and are maintained per covering, method and room type. They are ranges, not single figures: within the range, equipment, soiling and accessibility are decisive.

Does the calculation also apply to a cleaning company?

Yes, the calculation method is the same. Only the hourly rate, the management and material share and the margin differ. For providers, the calculation is above all the basis for a quote that stands up to scrutiny, see Solution for cleaning companies.

How often should you recalculate?

With every structural change, with a change of use and before every tender. Without such triggers, a review every three to five years makes sense so that areas, intervals and quality requirements match actual operations.

Conclusion

Cleaning calculation turns a gut decision into a verifiable calculation. Area, performance value, interval, operating weeks and hourly rate are enough to justify the effort for every room; difficulty factors and special cleaning close the gap to reality. Especially in the public sector, where funds have to be justified, this is a decisive advantage. Software such as easyCAFM automates this calculation on the basis of proven standard values, from more than 17,000 calculated properties.

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