What it means
A maintenance backlog contains work accepted for future action, and if managers see only the total number of jobs they cannot tell whether the team is keeping up or letting old items accumulate. Age bands, such as 0-7 days, 8-30 days and over 30 days, show where work is getting stuck.
Start with consistent definitions, because the clock may be measured from when the fault was reported, when a technician confirmed it, or when a work order was approved. A useful view often keeps all three timestamps, since pausing the clock while waiting for parts may explain the delay but should not erase the customer's or asset's elapsed waiting time, so status and cause should be shown separately from total age.
Segment the backlog by criticality, asset, site, work type and owner, because safety-related defects and legally required inspections need escalation through their own rules, not a simple average-age target. Look at work orders with no owner or next action, repeated postponements, and jobs closed and reopened without real completion.
Backlog ageing can reveal constraints, as work may await a specialist, a spare part, customer access, a downtime window or a funding decision. Record the blocker and a realistic next date, and do not mark jobs complete simply because a contractor was dispatched; verify the actual repair and any necessary testing.
Use a weekly review of the oldest and highest-risk items, with an owner for every decision, compare incoming work with completions to assess whether the backlog is growing, and report overdue items against service commitments in addition to general age. There are two useful views of age: the age of work still open today, and the completion time of jobs closed in the period.
The second view can improve while very old jobs remain untouched, so use both, and for high-risk assets review individual work orders rather than relying only on an aggregate statistic. An ageing report makes neglected work visible, but it must lead to prioritisation and action, not a race to make the dashboard look younger.
In practice
Real-world examples.
Example
A hotel has 40 open maintenance jobs, but five safety-related jobs older than their response target receive immediate management review.
Example
A factory's oldest work orders all await one imported bearing. It changes spare-parts planning rather than simply asking technicians to close jobs faster.
Example
A facilities manager keeps an agreed low-priority repainting task open with a planned date and visible reason, while a newer water leak takes priority.
Formula
Calculation
Open work order age = Reporting date - Original accepted request date
Worked example. An invented site reviews work on 30 September. A repair request accepted on 1 September remains open.
- Open work order age = 29 calendar days, using the site's stated date convention.
- If the repair was paused for ten days awaiting a part, report the reason but keep the 29-day total wait visible.
Agree whether partial days, weekends and holidays are counted before comparing the result with a service target.Case study
Seen in the real world.
This illustrative and entirely fictional example follows Vale Properties, an invented manager of small office buildings. Its monthly dashboard showed that 90% of work orders closed within five days. A tenant complained that an air-conditioning problem had been open for six weeks. The dashboard measured only jobs completed that month and ignored the age of jobs still open.
Vale added an open-backlog ageing report by site and priority. The old air-conditioning job had been transferred between teams twice, resetting its displayed date each time. The manager restored the original request date, checked the repair history and found that a part order had never been approved. She assigned an owner, secured the part and kept the tenant informed of the next steps.
Other aged items were reviewed for safety and customer impact rather than handled strictly by order of age. A later report showed both completed-job speed and the old open jobs. Vale changed its transfer process so reassignment did not reset the clock, and reviewed blocked orders weekly. The improved measure did not fix equipment itself, but it made a neglected problem hard to miss again.
Watch out
Common mistakes.
- Resetting the age when a work order changes owner, status or schedule.
- Reporting only fast closed jobs while omitting old work still open.
- Prioritising solely by age and overlooking criticality, safety and service obligations.
Questions
People also ask.
When should the age clock start?
Define it consistently, preferably preserving the original request and acceptance timestamps even if approval or assignment occurs later.
Should waiting for parts pause the age?
Show the reason and any contractual clock rule separately, but retain the total elapsed wait for operational visibility.
Is average backlog age enough?
No. Age bands and individual high-risk or overdue items reveal problems an average can hide.
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