Minimizing Materials Wastage in Construction- A Lean Construction Approach

K. Agyekum1, J. Ayarkwa2 and T. Adjei-Kumi3
Department of Building Technology
1,2,3,Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
E-mail: agyekum.kofi1@gmail.com
ABSTRACT: It is commonly acknowledged that a very high level of waste exists in construction.
Since construction has a major and direct influence on many other industries by means of both
purchasing inputs and providing the products to all other industries, reducing waste in the
construction industry could yield great cost savings to the society. This paper aimed at
identifying the main sources and causes of materials waste on construction sites arising from
storage and handling of high waste generating building materials and employing the Lean
Construction approach to reduce such waste. The findings in this paper are based on a
structured questionnaire survey of 226 building construction organizations and consultants in
the Ghanaian building industry. The findings revealed that materials storage and handling,
operational factors, design and documentation factors and procurement factors are the main
sources of waste on building construction sites. Among the causes of materials waste are last
minute client changes, errors by tradesmen, purchased products that do not comply with
specification and lack of onsite materials control. The findings further showed that timber,
cement/mortar, concrete and blocks are the four key materials that have the highest level of
wastage on building sites. Recycling of some waste materials on site, re-using of surplus
materials where appropriate and preventing the occurrence of waste are recommended to reduce
waste. Minimizing material wastage would not only improve project performance and enhance
value for individual customers, but also have a positive impact on the national economy.