Investigation of cost impact of construction materials wastages on site during operation. A case study of addis ababa city administration saving houses development enterprise.

Abstract

The building construction industry in Ethiopia in general has been found to be among the main consumers of resources and energy. Moreover, the materials wasted on construction site during operation exceed the allowance level considered during design stage. This materials waste is shooting up the cost of the house, which is challenging for the government who constructs the house and transfer to the registered house seeker. Due to this, the house seekers failed to afford the cost of final project and the contractor’s profit was minimized. The objectives of the research were to investigate how much construction materials wastage was costing housing project budgets in Addis Ababa city administration saving houses development enterprise. The study identify the mostly wasted construction materials during operation, the major cause of construction materials wastage, and suggesting some frame work to mitigate the effect of construction materials wastage on housing project cost. The main tools for the collection of data include questionnaires, interviews, site visit and observation that used to identify the mostly wasted materials, cause of construction materials wastage during operation and to what extent materials wastage was costing housing project. The findings of this research indicate that the first five mostly wasted construction materials on housing construction sites are Concrete hollow block, Timber formwork, Cement, Reinforcement bar and Tiles. It is also concluded that the three most important factors contributory to construction material waste generation on building sites are materials handling and storage, design change and revisions and operation. The study revealed that the cost of waste incurred, on average in these four sites is 7.6 % of the total cost, ranging from 5.2 % to 9.5 %. This indicates that minimization of material waste in the housing construction projects would therefore lead to substantial saving on the purchasing cost of building materials, in addition to savings on dumping costs. The results of this study recommended that there is a need to establish a new construction waste department to develop waste management policies and develop the effective strategy to reduce construction waste.