An off-site snapshot methodology for estimating building construction waste composition - a case study of Hong Kong

Waste composition analysis is essential for implementing appropriate management strategies. In Hong Kong, on-site waste quantification is often not practical due to site space limitation at construction sites. In addition, as the construction waste problem urgently needs addressing, reliable waste generation rates need to be derived over a short time. To address these two issues, this study presents an off-site snapshot methodology for estimating construction waste composition. Three construction sites, at the initial stage, mid-stage, and end stage respectively, are selected for illustrating the proposed snapshot methodology. It is found that the composition of inert and non-inert waste varies significantly at different construction stages. Non-inert waste is an important component of building construction waste, of which wood & timber waste contributes the largest proportion. Following wood & timber waste, metal waste is the second largest source of non-inert waste. Results show that the proposed off-site snapshot methodology can sufficiently solve the problem of limited on-site sorting space and derive reliable detailed waste generation information over a certain short time.