Do The Numbers:
The Mathematics of Cleaning:

The devastating events of October 2008 have left the stock market and the banking system reeling. The Canadian dollar is down to 80 cents and gasoline prices are still at depressing levels. Meanwhile, cleaning service providers wait to see how these events will affect their operations.

Energy prices impact the prices of most products used in our industry and this, with the downturn in the economy this is likely for a year or more, will put pressure on both in-house and contract cleaning operations to be as efficient as possible. When outsiders look at cleaning services, they tend to see them as mop and pail organizations having few, if any, significant financial issues to consider. We in the industry know that the opposite is true, cleaning is a mathematical operation, and to be successful you have to do the math – and do it right!

Every part of a cleaning service involves mathematical calculations that, if ignored, will lead to problems, some may be minor – such as shortages of supplies (although to the client a shortage of restroom supplies is a major issue) – and some major resulting in business failures or staff lay-offs. Effective cleaning management starts with the basic formula:

Annual cost of cleaning = (Cost of Labour and Materials x Task Time x Frequency) Area

Labour Cost includes all overhead costs for benefits, absence relief, tools, equipment and supervision, (dollars per hour).

Cost of materials delivered to the site, needed to do the task.

Task time in hours and minutes to perform the task.

Frequency is how often the task is done per year.

Area is the size of the area being cleaned, in square feet or square metres.

Virtually all other calculations in the cleaning industry are done to provide the data for this formula.

Dilution rates are intended to ensure that enough product is used to ensure adequate cleaning, guesswork such as the “glug glug” method wastes product, money and time. In addition, in areas where water is soft dilution rates should be increased by as much as 50 per cent as manufacturers dilution rates are established for the hardest water likely to be found.

For example, you need to choose between two neutral detergent products that have different prices per four litre jug and also have different dilution ratios. Since you have 20 employees each using four, 10 litre bucketsful-per-day you need to know the ‘in use’ cost per litre and multiply that by the number of bucketsful used per year. The formula is as follows:

Cost per four litre jug x (20 x 40 x 260) the answer is in dollars per year
((4 x dilution ration) + 4)

For floor finishes and sealers, there are two types of calculations.

To get the cost per 1000 sq. feet or cost per 100 sq. metres, you need to compare coverage rates. The formula is as follows:

 Cost per litre per a 20 litre pail that is Cost per 20 litre pail
Coverage per litre (coverage x 20)

To decide how many pails to ship to the job site you need to compare the coverage per 20 litre pail of each product multiplied by the number of coats needed and the area being coated. This is important because if you ship too few, time is lost waiting for location instead of being in your store room ready for the next job. The formula is:
Are to be covered x number of coats for example 200 sq. metre x four costs = 5.7 pails (take six)
(Coverage in sq. metres per litre x 20) 7 x 20

Choosing or justifying equipment such as an autoscrubber or propane burnisher involves comparing the productivity of the machine versus the method you currently use multiplied by the area being cleaned or burnished multiplied by the number of times the work is done in a year all multiplied by your current labour cost. Productivity data is available from ISSA (as you janitorial supplier for a copy). A typical calculation to identify the potential savings achieved by the purchase of more efficient equipment is:

Production rate of autoscrubber in sq. feet per hour multiplied by: Your hourly labour cost)
Area cleaned in sq. feet x number of times cleaned per year

Compare this with the annual cost using your present method – e.g. mop and bucket.

Production rate of mop and bucket in sq. feet per hour multiplied by: Your hourly labour cost
Area cleaned in sq. feet x number of times cleaned per year.

(You can also use this formula to compare two similar pieces of equipment e.g. a 20 inch and a 24-inch machine to see whether going bigger is justified for your facility). The ISSA times are quite extensive and are based on average effort and real life productivity. It’s possible to compare dust mopping with sweeping and with vacuuming, or spray buffing with burnishing as well as window cleaning with different methods. At last count there were 447 standard times in the handbook and more are being added yearly.

In addition to the ISSA times there are task times published by APPA dealing with the cleaning of specific area types, such as classrooms, shower rooms, corridors, stairwells, offices, laboratories and a range of room types with different floor finishes. APPA developed a cleaning standard incorporating times and frequencies needed to achieve a range of quality levels and published the data in “Custodial Staffing Guidelines for Educational Facilities.” The APPA standards have been adopted by the U.S. Green Building Council for LEED Building standards and are extremely useful for planning and justifying staffing levels.

Absenteeism versus inefficiency: Much effort is involved in attendance management programs designed to reduce absenteeism with the aim of reducing labour costs. There will always be a minimum level of absenteeism with the aim of reducing labour costs. There will always be a minimum level of absenteeism due to illness or injury that no program will reduce although chronic attendance abusers should always be targeted. If as much effort was applied to efficient time management on the job as there is to absence management the labour savings would be very significant. For example.

For a staff of 100 with an absence average of seven days per year the time loss is 7 x 100 x 7.5 hours… 5250 hours per year.

For a staff of 100 with time loss of 15 minutes each per day due to extended breaks and late starts or inefficient assignments the time loss is:

100 x 260 x 15 … 6500 hours per year
60

In discussions with custodial managers over several years, I’ve found that the typical time loss is more like one hour per day, now that really is an opportunity for cost reduction that should be addressed.

Simple calculator tools for the formulas listed that will save readers time and frustration are available to use at no cost on our web site at www.groupb.ca/Services.html click on ‘Supervisors Toolkit’. In the tight times that we are facing using guesswork is not a wise practice. Also, it’s always a good idea to remind your administration that there’s much more to custodial management than a mop and a bucket.