Abstract:
This study investigated construction wastes in residential construction projects. The study divided into 3 parts: the proportion
of incurred construction wastes, the causes of the wastes, and the guideline to reduce the wastes. The data was obtained by interviews
and questionnaires. Ninety samples from forty four residential construction projects located in Bangkok Metropolitan area were
collected. The results are summarized below.
It was found that construction wastes mostly occurred from seven categories of construction materials: lumber, concrete & cement,
wall blocks, steel, floor and wall tiles, roof tiles and containers of these products. The lumber and, concrete & cement categories incurred
the most wastes at 7-10 percents.
The causes of the wastes were divided into two groups; i.e., causes related to the management and causes related to the operations. Five
causes related to the management are the design changes, lack of material planning, inappropriate storage location, inappropriate usage of
products and ineffective communications. Three causes related to the operations are rework, lack of material usage plans and unskilled workers.
The guidelines to reduce wastes are material planning, material standardization, preparation of storage location, clear work orders, preparation
of construction, monitoring & control of the operation, and worker training.