Programmes. Unit 3: P lanning construction work processes and efficient use of resources in construction and the built environment.

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1 Unit : P lanning construction work processes and efficient use of resources in construction and the. Links This topic links to: HNC in Construction and the Built Environment Unit : LO; HNC Unit 15: LO. NVQ Unit 9: LO1. Programmes This topic guide examines the different methods for planning the time element of a project by producing a contract programme. Digital methods are examined so you have some knowledge and understanding of these methods versus manual techniques. You should obtain access via your employer to some programming software in order to gain hands-on experience of the capabilities, use and potential of such software. This topic guide will cover: the use of Gantt charts the critical path analysis method of programming the terminology used for contract programmes. 1

2 1 Programmes and schedules Gantt charts This is the most common form of managing a project s timeline. It allows the use of a simple visual method to control the sequence, duration and overall completion date for a construction project. The advantages of using this method are: simplicity ease of construction the strong visual message that it can be colour-coded for different classifications that it can be monitored through a vertical line from the top of the Gantt chart to the bottom that it can be understood by all that progress can be coloured on each activity. Gantt charts can be produced electronically using project management software, as Figure..1 illustrates. A Gantt chart consists of a series of bars, with each bar representing a work activity. The length of the bar indicates the duration of that activity with a start and finish time. Activities can be linked in sequence so one cannot start before the other has been completed. Monitoring is undertaken by using a vertical line which is moved across day by day and which reaches from the top of the Gantt chart to the bottom. At any time progress can therefore be measured against targets. Task Site set up Site clearance Asbestos removal Demolition Fencing and gates Access road Excavate foundations Concrete foundations Erect steel frame Cladding to roof Cladding to walls Windows and doors Figure..1: A Gantt chart. Time 7 days days 1 day days days Gantt chart Critical path analysis This technique is far more complex than the Gantt chart. It uses the following notation: nodes these are circles on the end of an arrow which contain information on float, node name, etc. arrows these are the lines that span between the nodes and indicate the direction of time and represent the activity.

3 Key terms Critical path the sequence of activities that have no flexibility in their sequencing; if there are any delays, there will be an effect on the overall contract completion date. Float the amount of spare time within an activity that will not affect the critical path or the end date of the contract. Time flows from left to right and the starting point is always zero. Each arrow has a duration on it. You have to work through the diagram and calculate both the shortest and the longest duration to complete tasks. The critical path has been indicated in red in Figure... The small, numbered boxes within each node represent the earliest start date and latest finish date of the activities. These can be used to calculate float. A days 6 E 6 days Figure..: A sample critical path analysis B C 1 day D 6 days 10 F G days Software techniques Many software programming techniques provide an extensive reporting facility. This produces a variety of reports, which may include: resourcing of activities costing reports activities started, in progress and completed critical tasks. Only by practising using such software can you truly appreciate what a powerful tool it is. Typical software that is commercially available includes Microsoft Project, Primavera and Asta Powerproject Planner. Programme terminology Resources Activities can be resourced from the method statement and all the quantities entered into a software resource application that enables tracking and monitoring of activities resources; this includes equipment, plant, human resources and their associated costs. Activities These are the construction operations represented by bars or arrows associated with a Gantt chart or critical path analysis diagram.

4 Timescales The duration of an activity is indicated by the length of a bar on a Gantt chart. Time runs from left to right on a critical path diagram. The length of the interconnecting lines can also represent time. Sequencing This refers to the logical sequencing of activities, for example excavation of a foundation will precede concreting. Dependency This refers to the dependency of one activity on another, for example a roof cannot be started if the steelwork is not in position to support the roof cladding. Portfolio activity (.) This assessment criterion requires that you produce a logical schedule of inter-related activities to enable a resource-efficient work programme to be prepared. You will need to undertake an analysis of a current pre-start tender document and establish a set of suitable tasks that could be used to construct the main contract programme. This set of activities must then be evaluated for its logic in sequencing within the programme so that progress is safe and planned efficiently. Portfolio activity (.5) This assessment criterion requires that you produce work programmes that efficiently control workflow, the use of resources, time and waste. Therefore you need to select a suitable format, for example manually drawn or using your company software, and produce this evidence to demonstrate your programming skills. You could produce an overall contract programme, followed by a series of weekly and daily detailed programmes on particular work activities. Portfolio activity (.) This assessment criterion requires some explanation of the logic and sequencing of the activities within your produced programme. You will need to explain how you have identified any inter related activities to enable a resource-efficient work programme to be prepared. Portfolio activity (.5) For this assessment criterion you have to explain the procedures for producing work programmes that efficiently control workflow, the use of resources, time and waste. This explanation should cover the type of programme that you are producing for a project.

5 Checklist By the end of this topic guide you should have completed the following working towards your learning objective of being able to produce method statements and programmes : produced some specific method statements for a range of work activities based on preferred organisational work methods assessed these work activities against the requirements of significant external factors that are associated with your project produced a logical schedule of inter-related activities to enable a resource-efficient work programme to be prepared produced method statements for planned activities that demonstrate that they efficiently control workflow, the use of resources, and time and wastage on the activities concerned produced work programmes that efficiently control workflow, the use of resources, and time and wastage on your project. Further reading and resources This website provides tutorials on a variety of management tools, including critical path analysis: Clark, W., Polakov, W. N., Trabold, F. W., The Gantt Chart: A Working Tool of Management (Nabu Press, 010) Haugan, G. T., Project Planning and Scheduling (Management Concepts Press, 00) Acknowledgements The publisher would like to thank the following for their kind permission to reproduce their photographs: Rough Guides: Roger Mapp (1) All other images Pearson Education Every effort has been made to trace the copyright holders and we apologise in advance for any unintentional omissions. We would be pleased to insert the appropriate acknowledgement in any subsequent edition of this publication. 5