The Crane Is Busy. Which Project Activity Really Has Priority?
Shared plant becomes a schedule risk when requests are prioritised by urgency or influence rather than programme impact, readiness and visible decision rules.
The short answer
When a shared crane or major item of plant is oversubscribed, priority should not be decided by whoever asks first or argues loudest. The project needs visible decision rules that consider programme impact, workface readiness, safety and access constraints, delivery commitments, downstream consequences and the value of recovery. The final allocation can remain a management judgement, but the basis should be explicit.
A crane is a good example because its capacity is indivisible in time. Two teams can both have valid reasons to use it, yet only one lift can happen in a given window. If the allocation decision is disconnected from the programme and readiness evidence, local productivity can improve while the overall project slips.
A project example
At 7:00 a.m. three requests compete for the tower crane. The façade team has a delivery truck waiting at the gate. The MEP contractor wants to move large plant to a roof zone before access becomes restricted. The concrete team needs formwork components for a pour on the current critical sequence. All three supervisors describe their work as urgent.
The crane coordinator can create a queue, but a queue does not answer which activity protects the project outcome. The façade delivery may incur waiting cost, the MEP lift may have a narrow access window, and the concrete sequence may control a downstream milestone. The decision requires project context.
That context comes from the same executable planning chain that connects the programme to live site work. Resource allocation is not a separate plant-management exercise; it is one of the mechanisms through which programme priorities become real.
Define priority before the conflict happens
Projects make better resource decisions when the criteria are agreed before a congested morning. Suitable factors can include critical or near-critical programme effect, whether all prerequisites are ready, whether a delivery or permit has a fixed window, safety constraints, the number of downstream activities protected, and whether the work is part of an agreed recovery plan.
No single factor should automatically win every time. A non-critical activity with a one-hour statutory access window may reasonably take priority over a critical activity that can move later the same day. The purpose of the rules is not to automate judgement; it is to make trade-offs comparable.
The project should also distinguish priority from preference. A team may prefer a continuous crane period because it is convenient, while the project may benefit from splitting the window to protect two milestones. Visible criteria help the discussion focus on project consequence rather than departmental ownership.
Readiness must qualify demand
A resource request should not be treated as fully valid until the receiving workface is ready. If the load is not prepared, the permit is missing, the destination is blocked or the follow-on crew is unavailable, allocating the crane can simply move waiting time from one place to another.
For each significant request, capture the activity or work package, location, required time window, load or task description, readiness conditions and consequence if missed. The level of detail can be light, but it should allow the coordinator to distinguish a ready priority from an aspirational booking.
This concept mirrors the wider workface control discussed in inspection passed, but the next trade still cannot start. A green upstream status is useful only if the conditions needed for productive next work are genuinely present.
Connect plant requests to programme activities
A list of crane bookings becomes much more useful when requests are mapped to programme activities or agreed work packages. The project can then see whether a conflict affects a critical sequence, a float-consuming activity, a recovery action or a low-consequence task.
The relationship should work both ways. Planners should be able to see significant resource constraints against the programme, and plant coordinators should see the programme context without reading the full schedule. Stable package and activity identifiers make that possible.
A project-centric ERP such as Saturn can help by maintaining common project, package, procurement and site context around resource decisions. It should complement, not replace, the professional planning and lifting controls required for safe construction operations.
Include deliveries and logistics in the decision
Crane time is often constrained by logistics rather than lifting capacity alone. Delivery slots, road restrictions, unloading areas, hoists, traffic marshals and storage space can determine whether a planned lift is feasible. A booking that ignores those dependencies may look efficient in a crane calendar but fail in practice.
For critical materials, connect the delivery commitment to the activity and requested lift window. If the supplier changes arrival time, the resource plan should show the consequence early enough to reallocate capacity. Conversely, if the crane window moves, procurement or logistics may need to change the delivery instruction.
This avoids a common failure mode: every function reports that it met its own plan while the material, crane and workface never became available at the same time.
Record why priorities change
Construction plans change constantly. The control problem is not change itself; it is invisible change. When crane priority moves, record a short reason such as access constraint, late delivery, critical recovery, safety hold, client instruction or unready workface. The reason can be coded and supplemented with a note for important cases.
That history helps the project learn. Repeated displacement of the same activity may reveal unrealistic planning, chronic readiness failure or a resource bottleneck. Repeated emergency priority for one team may indicate that its requests are arriving too late. Without the decision history, management sees only utilisation.
Utilisation can be misleading. A crane can be busy all day while the project loses time because it served the wrong sequence.
Use time windows, not only daily bookings
Daily allocation is often too coarse for highly shared resources. A realistic control can use time windows tied to expected duration and location. The goal is not minute-by-minute optimisation; it is enough structure to identify conflicts before they reach the radio channel.
Time windows also encourage teams to define the real need. A supervisor requesting “the crane tomorrow” may discover that two specific lifts between 10:00 and 12:00 are sufficient. That precision creates capacity for others and improves the quality of coordination.
Where uncertainty is high, identify provisional and confirmed windows. Confirmation should depend on readiness checks close enough to the work to be meaningful.
Five practical controls
1. Publish the priority criteria. Programme consequence, readiness, fixed logistics windows and safety constraints should be understood by all requesting teams.
2. Map requests to work packages or activities. A plant booking should have project context.
3. Confirm readiness before protecting scarce capacity. Unready work should not crowd out ready priority work without a conscious decision.
4. Record reallocations and reasons. The history reveals structural planning problems that utilisation reports miss.
5. Review recurring conflicts weekly. Use the pattern to adjust sequence, logistics or temporary plant strategy.
The most effective projects make this process predictable. Teams may disagree with a particular decision, but they understand why it was made and what evidence could change it.
What management should measure
Useful indicators include:
- percentage of high-priority plant requests linked to a programme activity or work package;
- protected crane windows lost because the workface was not ready;
- critical activities displaced by lower-priority work;
- repeated emergency bookings by package or subcontractor;
- waiting caused by delivery and crane windows not aligning;
- resource conflicts that remain unresolved inside the near-term planning horizon.
These measures are more informative than plant utilisation alone because they describe whether scarce capacity is supporting the intended project sequence.
Frequently asked questions
Should critical-path work always get the crane first?
No. Criticality is important but not absolute. Safety, fixed access windows, delivery constraints, readiness and the ability to reschedule within float can justify a different decision. The point is to compare consequences explicitly.
Is a crane-booking calendar enough?
A calendar shows capacity but not necessarily project priority or readiness. It becomes a control tool when bookings are linked to work packages, programme context, prerequisites and consequences if missed.
How far ahead should shared plant be planned?
Use multiple horizons. Major lifts and logistics constraints may need weeks of preparation, while daily confirmation should occur close enough to verify workface readiness. A rolling lookahead can identify conflicts early and a short-term freeze can create execution discipline.
Does this approach apply beyond cranes?
Yes. The same logic works for hoists, access platforms, temporary power, specialist crews, test equipment, traffic routes and other shared constraints. Any scarce resource should be allocated against visible project priorities rather than isolated requests.