--- title: "Planning need, tools, bar chart limitations" subject: "Project Engineering" chapter: 3 key: "semester_7/project_engineering:planning-necessary-tools-bar-chart-limits" source: https://www.bctengineer.com/q/semester_7/project_engineering/planning-necessary-tools-bar-chart-limits site: BCT Engineering --- # Planning need, tools, bar chart limitations Project Engineering · Chapter 3: Project Planning and Scheduling - Asked in: 2067 Asar (old course), 4+4 marks - Video: [Advantages and Limitations of Gantt Charts — What You NEED to Know Before You Use Them!](https://www.youtube.com/watch?v=cXUSVG46ufc) — projectcubicle - Answer checked by Claude Opus 5.5 (high effort) on 2026-10-14 - Page: https://www.bctengineer.com/q/semester_7/project_engineering/planning-necessary-tools-bar-chart-limits - Whole chapter: https://www.bctengineer.com/md/semester_7/project_engineering/chapter-3 ## Question 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. ## 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. ## Answer #### 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). ```text 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. ## Check yourself The answer's key points as multiple-choice questions, with the correct option and why. 1. Which reason justifies project planning? A. It makes site supervision unnecessary B. It arranges resources in time and avoids idle time and waste C. It guarantees zero risk D. It fixes the market price of materials Answer: B. Planning organises resources, coordinates parties and reduces delay and cost overrun. (Key point: Need of planning) 2. What is the main logical weakness of a conventional bar chart? A. It does not show dependence between activities B. It cannot show duration C. It cannot be drawn on a time scale D. It shows too much detail for small projects Answer: A. Without logic links, the effect of a delay on other activities is not seen. (Key point: Bar chart limitation) 3. In the example, why can't you tell how a 2-week delay in F affects H, I and J? A. Because F has no duration B. Because H and F are the same activity C. The bar chart does not show that H cannot start until F and G finish D. Because the chart has no time scale Answer: C. Missing dependence means the impact on successors and on the 24-week completion is hidden. (Key point: Example) 4. What else does a conventional bar chart fail to show? A. Start dates of activities B. Names of activities C. The overall length of the project D. Critical activities and float Answer: D. It cannot show which activities are critical or which, like G, have free time. (Key point: Float) ## Related in Project Engineering - [Planning tools, milestone chart, WBS](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aplanning-tools-milestone-wbs) — Project Engineering, chapter 3 - [Planning in dynamic environment; linked bar chart](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aplanning-necessary-dynamic-linked-bar) — Project Engineering, chapter 3 - [Bar chart advantages and limitations](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Abar-chart-advantages-limitations) — Project Engineering, chapter 3, asked 2× - [Planning, scheduling; linked bar chart](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Aplanning-scheduling-linked-bar-chart) — Project Engineering, chapter 3 - [Bar chart of irrigation project with milestones](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Abar-chart-irrigation-milestones) — Project Engineering, chapter 3 - [When to use bar chart, CPM, PERT](https://www.bctengineer.com/question.md?key=semester_7%2Fproject_engineering%3Abar-chart-cpm-pert-situations) — Project Engineering, chapter 3 ## Related in other subjects - [Bar chart vs CPM/PERT as planning tool](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Aplanning-tool-choice) — Construction Management, chapter 2, asked 3× - [Chart vs table; bar vs pie graph](https://www.bctengineer.com/question.md?key=semester_5%2Fcommunication_english%3Adifferences-chart-table-bar-pie) — Communication English, chapter 4 - [Function of project management in Nepal](https://www.bctengineer.com/question.md?key=semester_8%2Fconstruction_management%3Acpm-function-nepal) — Construction Management, chapter 1 - [Limitations of conventional tubes and TWT](https://www.bctengineer.com/question.md?key=semester_7%2Frf_and_microwave_engineering%3Aconventional-tubes-limitations-twt) — RF and Microwave Engineering, chapter 5