Why Backlogs Matter: Key to Efficient Maintenance Planning

Managing a work‑order backlog may seem routine, but without an accurate, up‑to‑date list, critical tasks slip through the cracks. Effective backlog management is the foundation of sound maintenance planning and scheduling.

Defining a Backlog

In practice, a backlog can mean different things. The most useful definition is a list of all approved work that has yet to be started. Some organizations measure it in trade‑hours, but a more meaningful metric is the number of weeks it would take to clear the backlog using available resources. This figure can include or exclude preventive maintenance (PM) work, depending on your needs.

The alternative definition—treating the backlog as simply the set of work orders that have passed their "required‑by" date—is misleading. Because maintenance teams typically have a fixed roster of tradespeople, the "required‑by" date is often an educated guess that can conflict with prioritization logic.

When a work order is created, its completion date hinges on its priority relative to existing backlog items and on future, as‑yet‑unknown work orders. Assigning a "required‑by" date should be reserved for those few tasks that truly have a hard deadline; otherwise the date will only add confusion.

In this article we adopt the first definition. Within the approved‑but‑not‑started backlog, you can further segment work into sub‑groups: the planning backlog (orders for which we’ve committed to purchasing or other resources) and the ready‑to‑schedule backlog (orders for which all materials and resources are on hand and work could begin immediately).

Backlog Filtering

Herding all approved work orders into one massive list is counterproductive. Instead, filter the backlog into logical categories:

Shutdown Work vs. Non‑Shutdown Work

Shutdown jobs remain in the backlog until the appropriate shutdown is scheduled—sometimes a year or more in advance. Keeping them hidden until that point prevents them from cluttering the ongoing work stream. Preparation for shutdowns, however, should be prioritized alongside regular tasks and managed separately for efficient planning.

Mechanical vs. Electrical (and Other) Work

Filter by the type of resource required—mechanical, electrical, or other maintenance crews. Each crew’s backlog should contain only its own work, with clear references to any support needed from other teams.

Preventive vs. Corrective Maintenance

Preventive maintenance (PM) should be pre‑planned, pre‑scheduled, and stored in the system with inspection instructions. While PM and corrective jobs compete for the same limited trades resources, they can be managed separately for clarity. Hiding PM work until the scheduled window keeps the backlog focused on what can be started right away.

By setting up PM orders in the computer system, you create a steady daily workload that locks the manpower for PMs, leaving them “untouchable” for urgent corrective work. This dual‑schedule simplifies overall resource allocation.

Backlog Cleanliness

Maintaining a clean backlog demands discipline: only jobs that will be completed in the near future should reside in the list. Remove completed orders, duplicate work requests, and low‑priority tasks that are unlikely to be acted upon.

A key practice is to close or mark work orders as "physically complete" on the same day the work ends (for routine work) or within a few days for major shutdowns.

Assign this responsibility to a dedicated maintenance role—typically the planner—who can quickly verify and update the backlog status without disrupting daily operations.

Backlog Size

There is an optimal backlog size. Too small a backlog forces tradespeople to chase ad‑hoc work, reducing productivity. Too large a backlog ties up materials, erodes confidence in schedule reliability, and encourages “emotional emergencies.”

For a typical 24/7 continuous‑process facility, aim for:

• total backlog ≈ 4 weeks
• planning backlog ≈ 2–4 weeks
• ready‑to‑schedule backlog ≈ 1–2 weeks

These figures mean that all materials for the ready‑to‑schedule items are staged onsite, ready to go—provided the schedule is followed faithfully.

Adding Work to the Backlog

All new work requests should be vetted by the area maintenance supervisor and operations coordinator each morning. Decide quickly whether a request is a “small job” that can be handled immediately, or a task that merits inclusion in the backlog. Unchecked, the backlog can become chaotic and lose value.

Backlog Management Software

Ideally, your maintenance management system (MMS) should handle backlog control. Unfortunately, many MMS platforms offer limited filtering and sorting capabilities. In practice, a well‑structured spreadsheet often outperforms a generic system for managing work lists. Download the data, filter, and share the curated list via a secure server.

Remember that MMS excels at cost tracking and audit trails; use it for those functions and rely on an integrated spreadsheet for real‑time backlog management.

In summary, managers must monitor backlogs closely—ensuring they remain clean, realistic, and near the optimum size—to maintain high operational efficiency.