After this chapter, you should be able to
- Explain how activity resource assumptions create a time-phased demand profile.
- Calculate daily demand, peak demand, overload days and total resource-days for a deterministic teaching schedule.
- Distinguish resource allocation, aggregation, smoothing, levelling and mobilisation planning.
- Use available float and hand-off evidence when moving non-critical activities to smooth demand.
- Explain why resource levelling can change activity dates, network criticality and project completion.
- Compare overtime, additional resources, method change, resequencing and fast tracking as schedule-compression choices.
- Document resource and compression decisions with capacity, safety, quality, cost, risk and approval consequences.
The decision: can the planned work actually be resourced?Source §Resource planning · Decision-led opening
A logic-valid schedule may still demand more people, plant, workspace, supervision or specialist capability than the project can provide. Resource planning connects each activity to a defined method and resource assumption, aggregates demand across time and creates evidence for smoothing, levelling or changing the plan.
Prerequisite checkSource §Learning sequence · Prior knowledge
Float before movement
A non-critical activity has two working days of valid total float. What is the first scheduling question before delaying it by two days?
- Whether the activity is inexpensive
- Whether its successor, calendar, constraints and shared float still permit the move
- Whether another project uses the same crew
Reveal answer and feedback
Whether its successor, calendar, constraints and shared float still permit the moveCalculated float is network flexibility, not automatic permission. Confirm logic, calendars, constraints, interfaces and governance before moving work.
Build the resource basis from the construction methodSource §Resource planning · Resource basis
Resource loading begins with the same method evidence used for duration estimating. Each activity needs a resource type, quantity or crew composition, working calendar, availability assumption and relationship to output. Generic labels such as labour or plant are too broad when different skills, licences, capacities or work fronts cannot substitute for one another.
- Resource
- People, plant, equipment, space, information, finance or other capacity required to perform work.
- Resource assignment
- A stated quantity or crew of a defined resource linked to an activity and calendar.
- Resource calendar
- The periods when a resource is expected to be available for project work.
- Capacity
- The evidenced amount of a defined resource that can be supplied in a period under stated conditions.
- Resource pool
- A controlled group of sufficiently interchangeable resources whose combined demand and capacity are monitored.
- Resource profile
- A time-phased view of demand, usually displayed by period and compared with capacity.
| Field | Question | Example evidence |
|---|---|---|
| Resource type | Which competence, plant class or work-front capacity is required? | Crew role mix or plant specification |
| Demand basis | How much resource is required and why? | Method estimate and production record |
| Timing | On which working periods is the resource active? | Activity dates and resource calendar |
| Availability | Is the required capacity committed and mobilisable? | Allocation, supplier confirmation or roster |
| Interfaces | Which shared plant, access, supervision or workspace creates conflict? | Logistics and interface records |
| Change rule | Who may move or substitute the resource assumption? | Schedule and commercial governance |
- Confirm the activity scope, method, quantity, duration and calendar.
- Define resource types at the level where capacity is genuinely interchangeable.
- Assign demand and record whether it is constant, front-loaded, back-loaded or staged.
- Aggregate concurrent demand by period and resource pool.
- Compare demand with evidenced capacity and identify conflicts.
- Resolve conflicts through authorised smoothing, levelling, capacity, method or sequence decisions.
Choose the controlled resource pool
Two activities both need an operator, but one requires a specialist licence that the other does not. How should demand be represented?
- Combine every operator into one pool
- Track the specialist capacity separately or through a controlled skill attribute
- Ignore the licence until mobilisation
Reveal answer and feedback
Track the specialist capacity separately or through a controlled skill attributeCapacity must reflect genuine interchangeability. Aggregating unlike competence can hide a real conflict.
Aggregate resource demand across timeSource §Resource loading · Demand aggregation
For a constant assignment, an activity contributes its stated demand to every active working period. Concurrent activities are summed for the same resource pool. More detailed models may use variable contours, shifts or partial periods, but the basis must remain traceable and consistent with the activity calendar.
R_t is total demand in period t and r_i,t is the demand contributed by each activity active in that period. Sum only comparable resource units under the same time convention.
r_i is the activity resource demand and d_i is its working duration. Moving an unchanged activity may alter the profile without changing its resource-days; changing method or duration can change both.
Build the base crew profile
Five activities require constant crews: structure uses six people for two days, drainage uses three for one concurrent day, envelope uses five for two days, services inspection uses four for one concurrent day, and finishes uses six for two days.
- Concurrent day one
6 + 3 = 9
Day one demand is nine people - Concurrent day four
5 + 4 = 9
Day four demand is nine people - Total resource-days
(6 × 2) + (3 × 1) + (5 × 2) + (4 × 1) + (6 × 2) = 41
Total demand is forty-one crew-days - Capacity comparison
9 − 6 = 3
The peak exceeds a six-person capacity by three people
Result. The base schedule has two nine-person peaks and two overload days. The profile identifies a decision need; it does not select the response.
| Day | Active activities | Demand | Six-person capacity | State |
|---|---|---|---|---|
| One | Structure and drainage | Nine | Six | Over capacity |
| Two | Structure | Six | Six | At capacity |
| Three | No modelled activity | Zero | Six | Available capacity |
| Four | Envelope and services inspection | Nine | Six | Over capacity |
| Five | Envelope | Five | Six | Within capacity |
| Six | No modelled activity | Zero | Six | Available capacity |
| Seven and eight | Finishes | Six | Six | At capacity |
Interpret resource-days
A flexible one-day activity moves from day one to day three without changing its crew or method. What happens to its resource-days?
- They increase
- They remain unchanged
- They become zero
Reveal answer and feedback
They remain unchangedThe move changes timing and possibly peak demand, but the activity still requires the same crew for the same duration.
Smooth demand within valid schedule flexibilitySource §Resource smoothing · Smoothing concept
Resource smoothing adjusts non-critical activity timing within verified float so that demand variation or peaks are reduced without changing the required project finish. The schedule objective remains fixed. Every proposed move must preserve predecessor and successor logic, calendars, constraints, access, information and shared-float governance.
- Protect the required completion and every critical or near-critical path.
- Use current float calculated from valid logic and calendars.
- Identify whether float is shared with other activities or governed by contract procedures.
- Check physical work fronts, information, inspections and successor hand-offs after movement.
- Recalculate the network and resource profile after every accepted move.
- Record the reason, authority, data date and affected assumptions in the schedule narrative.
Move two flexible activities into available capacity
Drainage and services inspection each have two valid working days of delay. Move drainage from day one to day three and services inspection from day four to day six.
- Drainage move
Day one: 9 − 3 = 6; day three: 0 + 3 = 3
The first overload is removed - Services move
Day four: 9 − 4 = 5; day six: 0 + 4 = 4
The second overload is removed - New peak
max(6, 6, 3, 5, 5, 4, 6, 6) = 6
Peak demand becomes six people - Completion
Critical activities retain their dates
Completion remains day eight
Result. The teaching profile fits six-person capacity without changing total crew-days or completion. Real moves still require interface and float validation.
Recognise true smoothing
Which result demonstrates smoothing rather than levelling?
- Peak demand falls and required completion remains unchanged
- Completion moves later to fit capacity
- The project scope is reduced
Reveal answer and feedback
Peak demand falls and required completion remains unchangedSmoothing works within available schedule flexibility while retaining the target completion.
Level resources when capacity is the controlling limitSource §Resource levelling · Levelling concept
Resource levelling treats capacity as a scheduling constraint. Activities may move beyond current float, split where the method permits, or follow different priorities. The resulting dates, critical path and completion can change. A levelled schedule is therefore a new forecast requiring logic, milestone and commercial review—not merely a smoother chart.
| Priority rule | Purpose | Limitation |
|---|---|---|
| Protect critical activities | Reduce immediate completion impact | May starve near-critical or constrained work |
| Earliest start first | Provide a reproducible default | Does not reflect strategic or physical priority |
| Least float first | Protect paths with little flexibility | Float can change after every move |
| Shortest duration first | Release capacity quickly | May fragment logical work fronts |
| Contract or access priority | Respect external commitments | Requires documented authority and evidence |
- Freeze the data date, logic, calendars and resource capacities used for the calculation.
- Apply a documented priority rule to each unresolved conflict.
- Move or split only where the construction method and governance permit.
- Recalculate dates, float, criticality and completion after every levelling run.
- Compare the levelled forecast with contractual milestones and commercial commitments.
- Record resource assumptions and unresolved capacity risk for management decision.
Recognise the completion trade-off
Demand still exceeds confirmed capacity after all valid smoothing moves. An activity must move beyond its float. What must be recalculated?
- Only the histogram colours
- Activity dates, float, critical paths and project completion
- Only total resource-days
Reveal answer and feedback
Activity dates, float, critical paths and project completionMoving beyond float changes the schedule forecast and can create a different controlling path.
Compress a schedule through explicit choicesSource §Schedule compression · Compression concept
Schedule compression seeks an earlier forecast without reducing authorised scope. It is considered after validating logic, durations and resource feasibility. Compression must target work that controls completion and must state the consequence for safety, quality, cost, coordination, fatigue, rework and risk.
| Choice | How time may reduce | Evidence and risk checks |
|---|---|---|
| Remove invalid waiting or constraints | Corrects an artificial schedule restriction | Confirm the removed condition is genuinely invalid |
| Increase or rebalance resources | Raises effective output on controlling work | Work-front capacity, supervision, plant, supply and productivity response |
| Overtime or additional shifts | Adds working hours or calendar periods | Fatigue, local rules, supervision, logistics, quality and diminishing output |
| Change method or plant | Changes production rate or sequence | Design, temporary works, competence, trials, approvals, cost and mobilisation |
| Resequence work fronts | Enables parallel or earlier starts | Access, information, hand-offs, workspace and changed criticality |
| Fast track overlapping phases | Starts successor work before all predecessor information is complete | Rework exposure, decision maturity and controlled interface release |
C_c and C_n are crash and normal direct costs, while D_n and D_c are normal and crash durations. The slope compares incremental direct cost per time saved only within a defined feasible range; it does not capture every project risk or indirect saving.
Compare a bounded activity crash option
A controlling activity can reduce from six to four working days by changing method. Normal direct cost is forty-eight thousand currency units and crash direct cost is sixty thousand.
- Maximum time reduction
6 − 4 = 2
At most two working days are available from this activity - Incremental direct cost
60,000 − 48,000 = 12,000
Additional direct cost is twelve thousand - Cost slope
12,000 / 2 = 6,000
Illustrative direct-cost slope is six thousand per working day saved - Network condition
Recalculate all paths after each reduction
Stop when another path controls or the bounded crash duration is reached
Result. The option supplies a comparison value, not an automatic instruction. Verify feasibility, project indirect effects, risk and approvals before selection.
- Validate the current critical and near-critical paths before selecting an activity.
- Remove logic or constraint defects before paying to accelerate work.
- Define the feasible normal and compressed method for every candidate.
- Compare incremental direct cost with time-related cost, revenue, milestone and risk effects.
- Recalculate the network after each change because another path may become critical.
- Authorise the revised method, resources, budget, risk controls and schedule basis together.
Choose the first compression target
Which activity should normally be tested first for a possible time-cost trade-off?
- The cheapest activity anywhere in the schedule
- A feasible activity on the current controlling path
- The activity with the most float
Reveal answer and feedback
A feasible activity on the current controlling pathOnly a controlling activity can initially move completion. Feasibility and path recalculation remain essential.
Explore smoothing before accepting a levelling trade-offSource §Interactive learning · Simulation sequence
The explorer uses the eight-day teaching profile. Predict the peak effect, move one flexible activity at a time, compare demand with stated capacity and decide whether smoothing is sufficient or a levelling decision remains.
Resource Profile and Levelling Explorer
Test how flexible-activity timing and available crew capacity alter peak demand, overload days and the interpretation of smoothing versus levelling.
- Learning sequence
- Review the nine-person base peaks · Record a peak-demand prediction · Move one flexible activity within its two-day allowance · Load the smoothed case and compare peak, overload and completion · Reduce capacity to identify when smoothing alone is insufficient · State the evidence and authority required for the chosen response
- Assumptions
- One interchangeable crew pool · Whole working-day assignments · Constant crew demand within each activity · Two non-critical one-day activities with two days of valid delay · Critical activity dates remain fixed in the smoothing model · No productivity, cost, split-activity or probabilistic effects
- States
- Base profile · Changed delay · Smoothed profile · Capacity conflict · Prediction checked · Invalid input · Reset
- Validation
- Implemented against deterministic teaching cases; independent technical approval pending
Move flexible work, test capacity and explain the schedule consequence
Predict first. Shift only activities with available float, then compare demand, overload and completion.
How will your changes affect peak demand?
Base resource profile loaded. Predict the peak direction before moving flexible activities.
The current profile exceeds the available crew on days 1, 4. Smoothing opportunities shown here are limited to documented delay on non-critical activities. If overload remains, a true levelling decision may move completion or require a changed method, sequence, capacity or scope assumption.
| Day | Active activities | Crew demand | Capacity | State |
|---|---|---|---|---|
| 1 | A, B | 9 | 6 | Over capacity |
| 2 | A | 6 | 6 | Within capacity |
| 3 | No modelled work | 0 | 6 | Within capacity |
| 4 | C, D | 9 | 6 | Over capacity |
| 5 | C | 5 | 6 | Within capacity |
| 6 | No modelled work | 0 | 6 | Within capacity |
| 7 | E | 6 | 6 | Within capacity |
| 8 | E | 6 | 6 | Within capacity |
Reflect before continuing
Which activity moved, which float or permission enabled the move, and which hand-off could invalidate it? If demand still exceeds capacity, would the defensible response change resources, method, sequence, scope or completion?
Record the resource decision as part of the forecast basisSource §Management interpretation · Decision communication
| Record | Required statement |
|---|---|
| Demand basis | Activity, method, resource unit, quantity, timing and source |
| Capacity evidence | Committed availability, calendar, competence and constraints |
| Conflict | Periods, magnitude, affected activities and resource pool |
| Response | Smoothing, levelling, added capacity, method or compression option |
| Schedule effect | Changed dates, float, paths, milestones and completion |
| Other consequences | Cost, safety, quality, fatigue, logistics, risk and carbon implications |
| Governance | Decision owner, approval, data date, revision and update trigger |
Communicate the unresolved conflict
After smoothing, confirmed capacity is five people but critical work still requires six. Which statement is defensible?
- The schedule is resource-feasible
- A one-person critical-work capacity conflict remains and requires capacity, method or completion decision
- Float will automatically solve it
Reveal answer and feedback
A one-person critical-work capacity conflict remains and requires capacity, method or completion decisionSmoothing cannot move fixed critical work in this model. The remaining conflict needs an explicit management trade-off.
Lesson synthesisSource §Learning sequence · Synthesis
Key points
- Resource planning starts with method-specific, time-phased demand and evidenced capacity.
- Concurrent demand must be aggregated within genuinely interchangeable resource pools.
- Resource smoothing moves non-critical work within valid flexibility while protecting required completion.
- Resource levelling treats capacity as a constraint and may change dates, criticality and completion.
- Moving unchanged work can reduce a peak without changing total resource-days.
- Schedule compression targets controlling work through feasible, authorised time-cost-risk choices.
- Every resource decision requires recalculation, interface review and a traceable forecast narrative.
Source references recorded by the supplied chapter
- Chartered Institute of Building — Accreditation and Education Framework.
- Loughborough University — Construction Engineering Management undergraduate curriculum overview.
- Royal Institution of Chartered Surveyors — Project Management sector pathway.
- Deakin University — Bachelor of Construction Management curriculum overview.
- Colorado State University — Construction Management undergraduate course descriptions and learning outcomes.
- All India Council for Technical Education — Model Curriculum for Undergraduate Degree in Civil Engineering.
- United States Government Accountability Office — Schedule Assessment Guide.