Cost Per Square Meter: Robot Scrubbing vs. a Crew Shift

Which costs less per square meter, a robot or a crew shift?

On a large, open floor cleaned every night, a scrubbing robot generally comes in below a manual crew per square meter. ScrubberGuide, a guide site, describes the same pattern, and the model below points the same way. The margin depends on inputs that differ from building to building, so the answer is only as good as the numbers you feed it.

Both options reduce to a cost per square meter. A manual shift is loaded labor cost per hour divided by square meters covered per hour. A robot carries a variable hourly operating cost plus a fixed block of attendance each shift for setup, tank service, edges and exceptions. The two lines cross at a break-even area, and finding that point is the real job.

Every figure below comes from a public source or is labeled as a vendor claim. Where sources disagree, we show the range rather than picking the friendliest number.

What does a manual shift cost per hour?

The Bureau of Labor Statistics put the May 2025 median for janitors and building cleaners at $17.71 per hour, or $36,840 per year. That is base pay. According to Stealth Agents, vendors and aggregators commonly apply a loaded multiplier of 1.35 to 1.65 times base wages, which brings the range to roughly $23.91 to $29.22 per hour.

Supervision is easy to leave out. Pay figures for first-line supervisors differ from one aggregator to another, and one reports $25.66 for 2024, so pull your own rate from payroll. Then count only the share of a supervisor's time the floor actually consumes, not the share shown on the org chart.

How much floor does each option actually cover?

Manual speed is the biggest lever, and it varies widely. According to Sproutmation, a robot vendor, a skilled walk-behind operator covers 8,000 to 12,000 square feet per hour in ideal conditions and about 6,000 to 9,000 in real facilities. Those are vendor figures, but the gap between ideal and real is the one that matters.

Robot specs run higher. According to a distributor page for autonomous scrubbers, the Nilfisk Liberty SC50 covers about 20,000 square feet per hour and the SC60 about 28,000. Minuteman lists its Roboscrub 20 at 24,500 square feet per hour, which it describes as a theoretical maximum in manual mode.

Rated speed overstates what reaches the floor. Sproutmation estimates real output at 50 to 70 percent of spec, while Monster Janitorial puts it at 70 to 85 percent of rated productivity. Taking the lower Sproutmation figure, an SC50 works out to about 10,000 square feet per hour, and that is the robot rate used in the example below.

How do you build the cost per square meter model?

Start with the crew. At $29.22 per hour and 6,000 square feet per hour, which is 557 square meters, the crew spends about $0.052 per square meter. At 9,000 square feet per hour, or 836 square meters, the same hourly cost falls to about $0.035. At the favorable end, $23.91 per hour and 9,000 square feet per hour gives about $0.029.

The robot side has two parts. According to Sproutmation, operating cost runs $1.50 to $3.00 per hour with amortized hardware included, against $25 to $30 loaded for manual labor. Attendance is the second part. ScrubberGuide's model assumes 45 to 60 minutes of person time per shift.

Run a 1,000 square meter night, about 10,764 square feet. At 10,000 square feet per hour the SC50 needs roughly 1.1 hours, so operating cost is about $1.62 to $3.24. Adding 45 to 60 minutes of attendance at $29.22 per hour brings the total to about $23.54 to $32.46, or roughly 2.4 to 3.2 cents per square meter. The crew's conservative figure is 5.2 cents.

Which inputs move the result most?

Productive rate moves the manual side the most. Lifting a crew from 6,000 to 9,000 square feet per hour cuts its cost per square meter by about a third, from $0.052 to $0.035. Moving the loaded multiplier from 1.35 to 1.65 raises the hourly cost by about 22 percent, a smaller swing across that span.

For the robot, attendance matters more as the floor shrinks. Each extra 15 minutes of tank service or exception handling adds $7.31 per shift at $29.22 per hour. On a 1,000 square meter night that is about 0.7 cents per square meter, and on a much larger floor it nearly disappears.

The break-even area is where the robot's fixed attendance spreads thin enough. Using $21.92 of attendance, $3.00 per hour of operating cost and the conservative crew rate, the crossover lands near 450 square meters, about 4,800 square feet. ScrubberGuide places its daily-cleaning threshold near 40,000 square feet, roughly 3,700 square meters. That gap is the lesson: clutter, staging, exception handling and lower effective speed push the crossover upward, and a model that ignores them flatters the robot.

What about consumables, water and downtime?

Consumables are the small lines that add up. According to Biocce, a scrubber vendor, brushes and squeegee blades need replacing every 3 to 6 months. Each option consumes pads, brushes or blades, and their replacement interval belongs in the model. Water use belongs there too, measured from your tank volumes and refill frequency.

Downtime is where models break. A robot out of service turns into either a manual shift for the missed area or a missed night. Put the probability of downtime and the cost of your fallback on separate lines, and decide in advance who covers the missed area.

This is where the service arrangement matters. Service Robot Co. leases robots on a 3-year term with one fixed payment quoted after a site assessment, and our nationwide US engineer network services every unit. That turns downtime from an open question into a contract line you can carry through the model.

Where does a manual crew still win?

Smaller, cluttered or irregular floors often favor people. According to ScrubberGuide, robots pay back on large, open floors cleaned daily, typically 40,000 square feet or more per night, and on smaller or cluttered floors a manual walk-behind is usually cheaper.

Biocce's vendor model for a 10,000 square meter warehouse puts manual mopping at $40,900 to $43,900 per year, a walk-behind scrubber at $12,350 and a ride-on at $9,250. Equipment costs are excluded and the model's assumptions are not stated, so read it as a direction rather than a verdict.

How do you test the model against your own floor?

Replace each vendor figure with a measured one before trusting the output. Collect these inputs from your own building.

A site assessment is how we gather these at a customer's facility before quoting a lease payment. Run the model with your numbers, then test productive rate and attendance first, since those two inputs decide the answer more than any others in this comparison.

• Loaded labor cost per paid hour for the crew, pulled from payroll with taxes and benefits included.
• Supervisor hours the floor consumes, not the supervisor's full salary.
• Measured manual speed from a timed pass over a representative section, in square meters per hour.
• Effective robot speed from a pilot run on your floor, with clutter and staging in place.
• Attendance minutes per shift, logged during the pilot, including tank service and exception handling.
• Consumable replacement intervals and downtime hours, taken from logs rather than estimates.