Construction waste modelling for residential construction projects in New Zealand to enhance design outcomes
Section snippets
Background
Construction waste minimisation is a global challenge. The waste produced from construction and demolition makes a significant contribution to landfill waste, estimated to be between 16 and 60% of landfill sites worldwide (Uangcharoenrat et al., 2019). With the construction industry being responsible for up to 50% of landfill waste in NZ (Designing Out Waste, 2017), putting NZ at the higher end of the scale internationally, the industry is an obvious target for change. Also, a survey conducted
Research methodology
Quantitative data drawn from direct measurement of waste quantities from 159 detached residential projects provides a basis for the study. Multiple regression was used as the primary research method, alongside trend and WGR analysis. This method allows the explanatory powers of the predictor variables to be isolated, and the effect on the response shown (Neter et al., 1990). Trend analysis allows an insight into the impact of time, while ratio analysis provides a simple mechanism to compare
Dataset
Table 2 provides a summary of the dataset—response variable (Y): waste quantity and predictor variables (xnum). Column headings 0–2 relate to the quantity of the dataset for x2 and x3 and denote the categorical variable x2 answer 0 = house, 1 = house and self-contained flat/granny flat/rental unit.
WGR analysis
WGR for the sample dataset produces a waste rate of 32. 2 kg/m2. The same dataset was reanalysed based on the number of stories in a house. This gives a ratio of 33.72 kg/m2 for a single level home
Conclusion
The WGR in timber-framed detached residential projects in NZ is 32. 2 kg/m2, which is approximately sitting in the mid-range compared to international findings based on reinforced concrete structures. The findings cannot be directly compared due to varying construction technologies, materials use, and industry practices. Nonetheless, the results from this study have produced detailed data for the NZ residential construction industry to understand design decisions have on waste generation, which
Declaration of Competing Interest
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
References (40)
- et al.
Critical design factors for minimising waste in construction projects: A structural equation modelling approach
Resour. Conserv. Recycl.
(2018) - et al.
Multi-variable regression analysis for the solid waste generation in the State of Kuwait
Process Saf. Environ. Protect.
(2018) - et al.
A field based methodology for estimating waste generation rates at various stages of construction projects
Resourc. Conservat. Recycl.
(2015) - et al.
Construction waste estimation depending on urban planning options in the design stage of residential buildings
Constr. Build. Mater.
(2016) - et al.
An empirical study of construction and demolition waste generation and implication of recycling
Waste Manage.
(2019) - et al.
A novel methodology to estimate the evolution of construction waste in construction sites
Waste Manage.
(2011) - et al.
Estimation of construction waste generation and management in Thailand
Waste Manage.
(2009) - et al.
A model for estimating construction waste generation index for building project in China
Resour. Conserv. Recycl.
(2013) - et al.
Benchmarking construction waste management performance using big data
Resour. Conserv. Recycl.
(2015) - et al.
Estimating construction waste generation in residential buildings: A fuzzy set theory approach in the Brazilian Amazon
J. Cleaner Prod.
(2020)