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Planning need, tools, bar chart limitations

Short answer

Project planning sets objectives, coordinates resources, and provides a control baseline. Planning tools include WBS, bar chart, CPM/PERT, milestone chart, S-curve, and resource histograms. Conventional bar chart limitations: it does not show activity dependencies or critical path; e.g., a house bar chart shows roof slab and plumbing parallel but does not indicate that plastering must wait for both, making delay impact invisible.

Why is project planning necessary in any project? List out the planning tools used in project management. Write down the limitations of the conventional bar chart, showing a suitable example of a bar chart.

Need of project planning

  • It sets objectives, scope, time and cost targets and gives direction to all parties.
  • It foresees problems and reduces uncertainty and risk.
  • It arranges resources (labour, machines, material, money) in time and avoids idle time and waste.
  • It coordinates client, consultant, contractor and suppliers.
  • It gives the baseline for monitoring and control.
  • It reduces delay and cost overrun, and helps to arrange finance.

Planning tools

  • Work Breakdown Structure (WBS) and Organisation Breakdown Structure (OBS)
  • Bar chart (Gantt chart) and linked bar chart
  • Milestone chart
  • Network techniques: CPM and PERT (also precedence diagram method)
  • Line of balance (for repetitive work) and S-curve
  • Resource histogram, resource levelling and smoothing
  • Responsibility matrix, checklists

Limitations of the conventional bar chart

  • Does not show the logical dependence between activities, so the effect of a delay on other activities is not seen.
  • Critical activities and float are not shown, so the manager cannot say where attention is needed.
  • Not suitable for large and complex projects; the chart becomes crowded.
  • Difficult to update; any change in logic needs redrawing.
  • Durations are single-point values; uncertainty is not considered.
  • Does not show resource or cost relations.

Example: bar chart of a house project (weeks).

                 0   4   8   12  16  20  24  (wk)
                +------------------------
A Site clearing |#                       
B Excavation    | ##                     
C Foundation    |   ###                  
D Plinth beam   |      ##                
E Walls+columns |        #####           
F Roof slab     |             ###        
G Plumb/electric|             ###        
H Plastering    |                ###     
I Floor,doors   |                   ###  
J Painting      |                      ##
                +------------------------

In this chart, the roof slab (F) and plumbing (G) start together, but the chart does not say that plastering (H) cannot start until both are finished. If F is delayed by 2 weeks, one cannot tell from the chart how H, I and J are affected, or whether the 24-week completion is in danger. It also does not show which activities are critical (here both F and G, which run in weeks 13-16 and must both finish before H) and which have float, as a network does.

✓ Answer checked by Claude Opus 5.5 (high effort)

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