Abstract
The construction industry is an important investment-led and dynamic sector that contributes positively to the developmental progress in any economy. However, the construction industry is seen as an ineffective sector owing to the bulky waste it produces. It is also regarded as a key contributor to the negative effect on the environment caused by extreme amounts of waste generated on- and off-site. This study assesses the quantities of waste generated, the factors influencing waste generation, the waste management approaches implemented, the adverse effects of waste and the benefits from construction and demolition waste management implemented in the Nigerian construction industry. The data used in this study were collected from both primary and secondary sources. The primary data were collected through survey questionnaires distributed via emails to the targeted respondents who are construction professionals while the secondary data were collected via the review of related literature. Out of the two hundred (200) questionnaires distributed, only one-hundred and sixty-eight (168) valid data were retrieved and used for the analysis. The collected data accounted for eighty- four per cent (84%) of the entire survey. Furthermore, the reliability of the research survey instrument was tested using Cronbach’s alpha coefficient reliability while a one-way analysis of variance (ANOVA) was conducted to test the hypothesis deducted to quantify the twelve (12) waste materials recognized as waste generated in Nigeria. For the first hypothesis, sig- values were greater than 0.05, which implies that the null-hypothesis (Ho) is valid. The findings show that the most waste generated include concrete, wood and reinforcement, while drywall and bitumen comprise the least amounts of waste generated in the Nigerian construction industry. The T-test carried out on the statistical inferential comparison of the mean variance between the quantity of waste generated on site and the allowable waste shows that the sig- value (0.020) is less than 0.050. This consequently implies that the null-hypothesis (Ho) is not valid. The exploratory factor analysis conducted indicates factors influencing the waste generation are classified into five groups which comprise poor coordination and communication, inadequate planning and design, inappropriate materials transportation and storage systems, inefficient procurement and contractual agreements, and poor project execution and supervision. The approaches employed towards the waste management were also grouped into three (3) which comprise practical legal framework and modular construction, sustainable procurement and material optimization, and proper construction detailing and design. The findings indicate effects such as burden on landfill sites, shortage of land for building construction, air, land and water pollution, release of toxin and emissions of greenhouse gas (GHG) as adverse effects of waste on the environment. The benefits fromwaste...
M.Tech. (Construction Management)