One of the most common questions facility managers face when planning cleaning services: "How many workers do we need?" The answer varies greatly from one facility to another, and a misjudgment — too many or too few — has real costs. This guide gives you a practical methodology to reach the right number.

Why Is Determining the Right Number Important?

  • Fewer than needed: Poor cleanliness, exhausted staff, recurring complaints
  • More than needed: Excess costs without real added value
  • The right number: Sustainable quality at a suitable cost

The Core Factors in Determining the Number

1. The total area

Area is the starting point. The general rough rule:

Facility typeCoverage rate per worker per shift
Ordinary administrative offices500 – 800 m²
Commercial complexes and corridors300 – 500 m²
Hospitals and healthcare150 – 300 m²
Factories and warehouses1000 – 2000 m²
Schools and universities400 – 600 m²

📌 An important note: These are approximate figures affected by many factors. Don't rely on them alone — use them as a starting point for the more precise calculation below.

2. The required service level

The service level directly affects the required number:

  • Basic service: Daily mopping + restrooms — the approximate number above suffices
  • Medium service: Daily + weekly + monthly — add 20–30%
  • Intensive service: All of the above + continuous cleaning during working hours — add 50–70%

3. The number of restrooms and the intensity of their use

Restrooms are a "major consumer" of workers' time:

  • A restroom serving fewer than 20 people: cleaning twice daily, time: 15–20 minutes
  • A restroom serving 20–50 people: cleaning 3 times, time: 30–40 minutes
  • A heavily used public restroom: cleaning every hour, needs a nearly dedicated worker

4. Human density and the nature of use

Type of useAdjustment factor
Light use (quiet offices)× 0.8 (fewer workers)
Medium use (ordinary offices)× 1.0 (the baseline)
Heavy use (service centers, banks)× 1.3
Very intensive use (restaurants, hospitals)× 1.6 or more

Calculating the Number Step by Step

A worked example: a 3,000 m² administrative building with 4 restrooms where 150 employees work:

  1. Area workers: 3000 ÷ 650 = 4.6 → 5 workers
  2. Restroom workers: 4 restrooms × 30 minutes × 3 times = 360 minutes = ~0.75 worker → 1 worker
  3. Basic total: 5 + 1 = 6 workers
  4. Service-level adjustment (medium): 6 × 1.2 = 7.2 → 7 workers
  5. Absence reserve (10%): 7 × 1.1 = 7.7 → 8 workers

💡 The result: This building needs 7–8 cleaners in the regular shift. This differs from similar facilities depending on the other factors.

Factors That Increase the Required Number

  • The presence of a large kitchen or canteen (+1 to 2 workers)
  • Large outdoor areas (courtyards, parking)
  • Extended working hours or multiple shifts
  • Floor types needing special care (marble, carpet)
  • Peak seasons when numbers multiply

Smart Team Distribution

Number alone isn't enough — correct distribution between areas increases efficiency:

  • Assigning clear areas to each worker (no overlap)
  • Focusing on high-traffic areas at peak times
  • A "floating" worker to respond to emergency requests
  • Rotating on difficult areas to prevent exhaustion

Conclusion

Determining the right number of cleaners is not guesswork — it's a systematic calculation that accounts for area, service level, and the nature of use. Investing the time to do this calculation accurately saves you the costs of overstaffing and the problems of understaffing.

Frequently Asked Questions

How do I know if the current number of workers is sufficient?

The most telling indicators: Are employees satisfied with the cleanliness level? Does the team complete all the daily checklist tasks? Are complaints piling up? If the answers are no/yes/yes — the number is probably insufficient.

Does the required number change with the seasons?

Yes, slightly. Summer in Saudi Arabia increases dust and outdoor contamination, and Ramadan increases the need in mosques and restaurants. Flexibility to increase staff seasonally is an advantage to negotiate in the contract.

Is using a specialized company better than direct hiring?

A specialized company saves you the hiring, training, and replacement during absences — and can adjust numbers flexibly as needed. Direct hiring may suit very large facilities that have sufficient administrative capacity.