A job that must finish in a fixed window needs enough cleaners. Total labor hours divided by the window, rounded up, gives the crew size to staff.
The example
12 labor hours, 3-hour window.
| A | B | |
|---|---|---|
| 1 | Item | Value |
| 2 | ROUNDUP(12/3) | — |
| 3 | Crew size | → 4 |
The formula
The formula:
How it works
How it works:
- Total labor hours = area ÷ production rate (one-cleaner hours).
- Divide by the available window and ROUNDUP to whole cleaners.
- A partial cleaner rounds up — you can’t staff 3.2 people.
- More cleaners shorten the window; fewer extend it — the trade-off is linear.
Crew size and time window trade off directly. The same 12 labor-hours can be 4 cleaners for 3 hours or 2 cleaners for 6 — pick based on the client’s access window and your labor availability. After-hours office cleaning often has a hard window (building locks up), forcing a bigger crew; flexible residential work can run lean. ROUNDUP always — a fractional cleaner means someone stays late.
Try it: interactive demo
Total labor hours and time window.
Variations
Actual finish time
With that crew:
Window for a crew size
Flip it:
Labor hours from area
The input:
Pitfalls & errors
Round up. A fractional cleaner means staffing the next whole person.
Labor hours, not clock. Use one-cleaner hours before dividing by the window.
Zero window. No window gives #DIV/0!.
Practice workbook
Frequently asked questions
How do I calculate crew size in Excel?
What's the actual finish time with a crew?
Why round up?
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