Budgeted Night Hours, Priced Against a Fixed Lease

How do you price an empty overnight shift?

An empty overnight shift still costs you something. If night floor care sits in next year's budget, that money is committed, and it stays committed on nights when nobody shows up to work the hours. The cost surfaces as overtime, a contractor invoice, or a floor that nobody scrubbed before the first delivery truck arrived.

Pricing that gap takes three inputs: the hourly rate you budget for the role, the night premium on top of it, and whatever you already spend to cover the hours. Add those up over a year, then set the total beside a fixed robot lease payment quoted after a site assessment. That comparison shows whether the money you already carry can pay for a robot.

Most sites find the answer is a range built from their own payroll records, not a single number. That is why the worksheet below starts with schedules and accounts payable, not with a vendor brochure.

What wage should anchor the math?

The U.S. Bureau of Labor Statistics reports a May 2024 median of $35,930 a year, or $17.27 an hour, for janitors and building cleaners, across about 2.4 million jobs in 2024 (according to the BLS Occupational Outlook Handbook, checked in November 2026). That is a national median for the occupation. It says nothing about your metro area, a union scale, or the night rate your payroll office actually uses.

Start with your payroll rate for the night role. Treat the BLS median as a sense check, the way an estimator tests a bid against a known unit price. If your rate lands well above or below the national median, record that gap in the notes beside the worksheet instead of burying it in the total.

How large is the night premium?

A 2010 Culpepper survey of 202 organizations, reported by SHRM, found that 92% of companies pay shift differentials to hourly staff. Of those employers, 49% add a flat amount per hour and 47% add a percentage of base pay. That survey is more than a decade old, so treat it as orientation, not as a current rate card.

SHRM reports that percentage premiums typically run 5% to 15% of hourly pay, while flat premiums run $0.50 to $1.25 an hour. Applied to the BLS median, a 5% premium is $17.27 times 0.05 per hour, and a 15% premium is $17.27 times 0.15 per hour. Run both calculations against your actual night differential before you trust either one.

What does the worksheet look like?

Work the sheet once per site, using twelve months of schedules and payables. Keep each figure in its own column so a reviewer can trace it back to a source. The night shift autonomous scrubber then enters the sheet as one comparison line against the annual gap.

• H: budgeted night floor hours per week still empty after overtime and contractor cover were tried. Count only what stayed empty, so no hour is counted twice.
• R: the hourly cost of those hours, meaning your payroll rate plus the night premium plus employer taxes and benefits. Ask payroll for the load factor instead of guessing it.
• G: weekly gap value, which is H multiplied by R.
• X: weekly cover spend on overtime and contractor invoices for the hours that were filled, pulled from payroll and accounts payable.
• Annual gap: (G plus X) multiplied by 52, the total cost of the night shift as your books already show it.
• Lease side: multiply the fixed payment from the quote by the number of payments in a year, then compare the result with the annual gap. Use the figure from the quote itself, not an estimate.

How should you read the result?

Read the result as a range, not a verdict. If the annual lease cost sits below the annual gap, the lease covers the gap on paper. If it sits above, the gap alone will not carry the machine.

In that case the next step is a smaller scope. One sensible way to start with one leased unit is the zone that loses the most hours, because that gives the worksheet real run data to test against.

Where does a lease quote enter the picture?

Service Robot Co. offers commercial robot leasing through financing, on a 3-year lease with one fixed payment quoted after a site assessment. We do not quote before we walk the floor, because the floor decides the machine, its route, and where it charges.

We are OEM-neutral. We pick the right robot across manufacturers, then deploy, integrate, train staff, and service every unit through our nationwide US engineer network. That gives the worksheet one counterpart to ask questions of, from the site walk through the lease end.

What do the numbers leave out?

Industry totals do not settle the math either. According to a VietnamPlus report of IFR figures, professional service robot shipments rose 24% to almost 250,000 units in 2025, with cleaning robots ranking third and floor cleaning the main application. Separately, the IFR's October 2025 release said its professional cleaning segment grew 34% to more than 25,000 units in 2024 (according to BusinessWire).

Those are two separate reports, so treat each year as its own data point rather than a trend line to extend. Market growth shows where the industry is heading. It does not tell you what your floor should cost.

• Start, check, and close-out time. Someone still confirms the route is clear, the charging spot is free, and the unit is ready before and after each run.
• Fault response. A stopped unit at 2 a.m. needs a named person, a contact path, and a remote or on-site fix. Downtime starts when the unit stops, not when someone notices.
• Floor readiness. Loose cords, staged pallets, and fresh spills stop a route and cost the shift regardless of who runs it.
• Cleaning quality. Logged hours say nothing about passes made or edges left. Check coverage on the floor, not only in the log.
• Lease-end condition. A 3-year robot lease needs a condition check at return, and that cost belongs in the budget from the first day.
• Benchmark age. The BLS and SHRM figures above are national, dated, and generic, so replace them with your own data wherever you can.