Planned preventive maintenance is easy to describe and hard to size. Every building has a version of it, usually inherited: intervals somebody set years ago, a list that grew by addition, and a cost that appears once a year in a budget line nobody interrogates. This page is about the two questions worth asking of an inherited regime, which are where the intervals came from and what the whole thing costs in hours, and about doing the arithmetic before deciding whether the answer is more software or fewer visits.
Where an interval should come from
Three sources, in order: anything statutory that applies to the asset, the manufacturer's instructions, and the duty the asset actually sees in your building. The third is the one inherited regimes ignore: a plant room serving an empty floor and one running at capacity are on the same quarterly interval because they were commissioned together. Adjusting for duty is where most of the saving in a maintenance budget sits, and it needs the register to say what each asset actually does.
What the regime costs, in hours rather than in a contract price
A contractor's price tells you what they charge. The hours tell you what the regime demands of your site: attendance, escorting, plant room access, the defects raised and recorded afterwards. The check sheet on this site works those from your own numbers, and the answer is often startling for buildings whose asset list has grown for a decade without anybody totalling it.
When more planned maintenance stops paying
Preventive work pays until it does not: past a point, more frequent servicing on low-duty plant buys nothing except more visits to record. There is no universal threshold, and anybody who offers one is selling something. What is knowable is your own trade-off: run the sheet at two intervals, look at the hours, and set that against what the failures actually cost you when they happen.
Questions people ask about planned preventive maintenance
What is planned preventive maintenance?
Maintenance carried out on a predetermined interval to keep an asset working, rather than in response to a fault. In British usage it is more often written planned preventative maintenance, and the two mean the same thing.
How often should planned maintenance happen?
It follows the statutory requirement if there is one, then the manufacturer's instruction, then the duty the asset sees. This site publishes no interval table because the third input is yours.
Is planned maintenance cheaper than fixing failures?
Usually, up to a point, and the point is different for every asset. The arithmetic worth doing is the hours the regime costs against what the failures it prevents cost you, which is a calculation about your building rather than about maintenance in general.
What does the regime have to produce?
Evidence: a completed visit against each asset that was due, dated, with the defects it raised. Without that, the regime exists in a calendar rather than in a record.