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Friday, October 09, 2015


A company wants me to bid the floor cleaning of a 300,000 sq. ft. warehouse using their rider scrubbing machine, so I can take the cost of using their equipment into consideration for my price. The actual amount of cleanable space is 150,000 sq. ft. Charging $.04 per sq. ft., the monthly billing would be $6000. The hiring manager says it takes the current guy about 3 hours a night. If I charge $18/hr., my bid would be about $1080 a month. I know which proposal the hiring manager would prefer, but which proposal should I use? I am not worried about my overhead.


You can figure it either way and, obviously, the manager hopes you will agree to the lesser hourly charge. Your figures seem to indicate a five-day a week service, so let’s run some numbers. Three man-hours a night for a week equals 15 hours a week. At $18/hour that comes to $270 a week or $1170 a month in equal payments. This is about $.008 per sq. ft. which is quite low when you consider your costs.
Even discounting overhead, you have $10 per man-hour basic pay, $2 labor burden (20%), the cost of detergent, pads, mops, etc. By the time you get done, you may be clearing only one or two dollars a man-hour at the $18 rate. Is clearing $10 a night or $50 a week a good return considering the management time for a job such as this?
Then there is the time factor. The manager says the job takes about 3 hours, but the ISSA Cleaning Times for a 36” rider scrubber says you can expect to cover about 23,000 sq. ft. each hour. Using your 150,000 sq. ft. figure, that means about 6.5 hours for that machine to do the scrubbing. That is over twice the time you have been told it takes. Is the rider wider than 36 inches? Is the “current guy” skipping something?
There is the matter of sweeping to clear the floor of debris commonly found in a warehouse, pieces of cardboard, wood from skids and pallets, tracked-in grit, etc. Don’t rely on the scrubber to pick up debris unless it is designed as a sweeper, too. If not, where is the sweeper time figured in? And the time to clean up the mess in the pickup tank?
What if their (the warehouse’s) machine dies? Would it not be a good idea to have a backup machine lined up to rent for the duration of the repair or part’s replacement? Where is the money coming from to pay for that? Who pays for the repair? Who does the maintenance on the machine? Who cleans it?
You need some more answers. How long is it actually going to take to clean the floor with the supplied machine? How much detergent will you use every night? What will it cost, even in bulk? What will a backup unit cost to rent, and is one even available to you? How will the floor be swept and how long will that take? Where are the water sources and the dumping facilities? Will the batteries run the machine for as long as the floor will take to clean? Who is going to do the touch-up mopping and how long will that take?
At $6000 a month, the 3 hours per night figures out to $92 per hour, which looks high. However, if the job really takes 7 man-hours a night to do what is required, then that figure quickly drops to $39.50 an hour and that is not extravagant. I hope this helps you work through the problem and discover the realities of the job. Once you nail down the requirements and the realistic production times to do what is needed, you will be able to calculate a bid price that is fair to both you and the manager you need to please.
Lynn E. Krafft, ICAN/ATEX Associate Editor