Night Labor Hours vs. a Three Year Lease: A Worked Method

The short answer: price the night first, then the lease

Night cleaning costs more than the hourly wage on the timecard. A floor program carries paid hours, the gap left by unfilled shifts, overtime when someone covers those shifts, and the supervision time a robot would still need. Add those into one weekly figure, carry it across the weeks your site actually runs and across the 36 months of a lease, and you have a baseline.

Then set that baseline against one fixed robot lease payment. Service Robot Co. quotes that payment on a three year lease after a site assessment, so no lease figure appears here. The steps below use placeholders you fill in from your own records, and the result is only as good as those inputs.

Which five inputs do you need?

Pull these from payroll, your shift schedule and your work order log before you open a spreadsheet. Give each one a letter so every formula stays readable.

• H: paid night cleaning hours per week, taken from timecards for shifts that clean
• U: unfilled night shifts per week, averaged over at least 12 weeks
• L: loaded hourly cost, meaning wage plus payroll taxes and benefits
• O: overtime premium, the extra cost when staff already on the clock cover a shift
• S: supervision hours per week that a robot program would still require

What wage baseline should anchor L?

Start with a published reference, then replace it with your own data. The BLS Occupational Outlook Handbook gives a 2024 median pay of $35,930 a year, or $17.27 an hour, for janitors and building cleaners. It counts about 2.4 million jobs in 2024 and projects 2% growth from 2024 to 2034, which it calls slower than average.

That wage is the floor of L, not L itself. Payroll taxes and benefits sit on top, and local pay may differ from the national median. Where your payroll records exist, use them. The handbook also notes that entry into the occupation generally needs no formal credential and only short term training on the job.

How do you turn hours into a weekly cost?

Work out two weekly totals. The first is the paid cost of the night program, H times L. The second is the cost of unfilled shifts, U times shift length times L times one plus O. An empty shift that another worker covers at overtime costs more than the same hours at a normal rate, which is why O belongs in the formula.

An uncovered shift that nobody works carries no wage, yet the floor still goes uncleaned. That cost shows up in complaints, slip risk and deferred work, and it is real even when no one invoices it. Record it as a note beside the total rather than forcing a dollar value onto it.

Then subtract the supervision you would still pay, S times L. The result is the weekly amount a robot program could plausibly displace: H times L plus U times shift length times L times one plus O, minus S times L.

How do you carry the baseline across three years?

Multiply the weekly displaceable amount by the weeks your site really runs in a year. Use your operating calendar, not 52 weeks by default, because closures, holidays and seasonal shutdowns change the total. Keep that annual figure on its own line so the labor side is visible before any lease number enters the sheet.

Then multiply the annual figure by three for the lease term. If you expect wage increases, show them as a separate sensitivity line and document the rate you use. Do not bury a raise inside L, since a reader cannot check it there.

What does the lease side need to show?

The lease side has two inputs: the fixed payment quoted after the site assessment, and the term, which is three years. Total lease outlay equals that payment times the 36 months. Once the quote is accepted, that payment is the number that holds, so the lease side of the math stops moving.

Read the quote for what it includes before you compare totals. RoboCare service covers the lease term, so ask how dispatch, repair and remote triage are handled inside that payment, and do not add a separate maintenance line the quote already carries. If another lease option excludes service, add that cost to its side before judging.

Where does a floor robot leave labor in place?

A floor robot covers open aisles, corridors and large floor areas. Restrooms, stairs, trash pickup and detail corners often stay with staff, so S can be larger than expected. Walk the zones during the site assessment and count the leftover minutes as hand work or supervision, not as robot savings.

Route length matters too. A robot that needs longer than the shift to finish a zone will leave part of the floor unfinished, and that gap belongs in the numbers as a missed pass, not hidden inside an optimistic H. Overnight cleaning with no operator works only when the zone map fits the hours available.

Do market figures change the math?

They describe the category, not your floor. According to the World Robotics 2025 release reported by Business Wire, professional cleaning robots sold more than 25,000 units in 2024, up 34%, mostly for floor cleaning. The World Robotics 2026 release, reported by Kyodo News PR Wire in October 2026, puts professional service robot shipments up about 24% to nearly 250,000 units in 2025, with professional cleaning robots ranked third by segment.

Two cautions apply. Both figures come from press coverage rather than the full IFR report, and the 2025 release is reported as using a sample of 238 service robot suppliers, while the prior edition used 294. Do not combine figures across editions. Whatever the category does, H, U and S remain the only inputs that decide your comparison.

How do you read the final comparison?

Set the annual displaceable amount over the term beside the total lease outlay. If the lease total sits below the labor baseline, check if it still wins at a lower U, because unfilled shifts are the input most likely to swing. If the lease total sits above, check S and the zone map before rejecting the option, since a larger supervision line can reverse the answer.

Run three cases: your average, your best recent 12 weeks, and your worst. A comparison that holds only in the worst week is a warning, not a result. A site assessment comes before any quote, so it is the place to test your zones against the actual floor.