Network analysis and building construction: Implications for timing and costing of activities

Abstract

The upsurge in building collapses in Nigeria recently has been a source of concern to builders, engineers, individuals and policy makers. Previous researches have observed many factors responsible for the menace, which includes; use of substandard product, poor design, and unskilled labour. None have adequately addressed the impact of timing and costing of stages in the building process as part of their key variables. This study was therefore informed to explore the cost and minimum expected time that will be required to complete the project. The data on the cost and duration of activities involved were obtained from ALMEGA, Nig. Ltd., a civil engineering company based in Lagos. Both critical path method (CPM) and project evaluation and review technique (PERT) were used for the analysis. The activities underwent crashing of both the time and cost, this paved way for the determination of critical path. Further analysis revealed that the shortest possible time for the completion of the analyzed building project is 55 days instead of the expected duration of 92 days. This means that through proper scheduling of activities, the expected completion time was reduced by 37 days. The additional cost associated with the reduction in timing is N830,000.00 ($5,355.00), which increases the initial expected cost required to complete the project from N3,290,000.00 ($21,226.00) to N4,120,000.00 ($26,581.00). Therefore, stringent adherence to the minimum possible time to complete a specific part of building process will trim down building collapses in Nigeria. Although it may not be the only antidote, but when incorporated to building plan will make a difference. Key words: Networking, building construction, crashing, time, cost, critical path method (CPM), project evaluation and review technique (PERT).