What a CMMS is, in plain words

A CMMS is software that holds the record of maintenance work. It stores what needs doing, when it is due, who did it, and what they found. CMMS stands for computerised maintenance management system, which is a mouthful nobody says out loud. Most people just say "our maintenance system".

That is the whole definition. The rest of this page is about what follows from it, because the definition is easy and the choice is not.

The four things every CMMS actually does

Vendors list forty features. Strip the marketing away and every one of these systems is built on the same four jobs. If a product does these four well, the rest is negotiable.

• •Holds a list of the things you maintain: buildings, rooms, machines, vehicles
• •Turns a problem or a schedule into a job somebody is responsible for
• •Captures what happened on that job, at the time, from the person who did it
• •Lets you answer a question about the past without going through a filing cabinet

The fourth one is why the software exists. A maintenance team with a whiteboard can do the first three. What a whiteboard cannot do is tell you, eleven months later, when that pump was last serviced and who signed it off.

What a CMMS is not

It is not an accounting system, though it will produce numbers accounting wants. It is not a building automation system: it does not control the plant, it records the work done on the plant. And it is not a replacement for knowing your buildings. Software makes a good maintenance programme visible. It does not make a bad one good.

CMMS, EAM, CAFM, IWMS: the acronyms, sorted

Four names for overlapping products, and the boundaries move depending on who is selling. The useful distinction is what the software is centred on.

• •CMMS is centred on the work: jobs, schedules, technicians, history
• •EAM is centred on the asset over its whole life, including purchase, depreciation and replacement
• •CAFM is centred on the building: space, occupancy, floor plans, moves
• •IWMS is the bundle of all three plus leases and property, sold to large portfolios

Most teams under a few hundred buildings need a CMMS. If somebody is trying to sell you an IWMS and you cannot name three things in the property module you would use, you are being sold a bigger number.

When you actually need one

Spreadsheets work for longer than vendors admit. The honest signals that you have outgrown one are specific, and none of them are about company size.

• •You cannot answer "when was this last done" in under a minute
• •Two people are maintaining two different versions of the schedule
• •Work is reported by walking to somebody rather than writing it down
• •You found out about a failed inspection from the inspector
• •The person who knows how the building works is retiring next year

What it costs

Pricing in this category is usually per user per month, somewhere between 20 and 100 US dollars for the seat of somebody who assigns and reports. Field technicians are often cheaper or free, and if they are not, ask why: a system nobody in the field uses produces nothing.

The number on the quote is rarely the number you pay. Ask what implementation costs, whether data import is included, what happens to the price when you add a second building, and whether the mobile app is a separate line. Those four questions move the total more than the headline rate.

The mistake almost everybody makes first

Teams buy for the reports and roll out for the office. Six months later the reports are fiction, because the people doing the work found the software slower than a notebook and went back to the notebook.

Judge any system by whether a technician will use it at four o’clock on a cold Friday with one job left. Not in the demo. Not in the training room. If it takes eleven taps to close a job, or it stops working in a basement, it does not matter how good the dashboard is.

How to run the selection

• •Write down the five questions you cannot answer today. Those are your requirements.
• •Give each shortlisted vendor one of your real rounds and ask them to build it during the demo
• •Put the phone in the hands of the technician who complains most, not the manager
• •Ask for a reference in your industry with roughly your number of buildings
• •Check what happens to your data if you leave, in writing, before you sign

What good looks like a year in

Not "everybody uses the system". That is an input. The outcomes worth measuring are that late preventive work is a number somebody watches, that finished jobs arrive with photographs nobody had to chase, and that an auditor asking about one room on one date gets an answer while they are still standing there.