Life cycle assessment of cement-bonded composite boards with municipal waste wood

The utilisation of waste wood in cement-bonded composites addresses pressing ecological challenges by diverting municipal waste wood from incineration. In this study, a life cycle assessment (LCA) was conducted on a pilot-sized wood-cement composite board (1 × 1 m²; 18 mm thick) incorporating 25 wt% waste wood converted into wood chips. Environmental impacts were quantified for standard categories, including global warming, acidification, eutrophication, etc., in accordance with ISO 14044 guidelines. The results showed that Ordinary Portland cement was the dominant contributor to all impact categories, whereas the waste wood had negligible cradle burden. The composite product achieved a global warming potential of approx. 10.7 kg CO₂-eq., substantially lower than comparable cement-based composite boards on the market (14–32 kg CO₂-eq.). Primary energy demand of the boards was 40–70% less than that of commercial alternatives, benefiting from the use of bio-based waste and a cleaner energy mix in production. The composite boards exhibited a favourable environmental profile while maintaining acceptable mechanical performance for non-structural applications, thus providing a sustainable outlet for municipal waste wood. The findings support the viability of upcycling municipal waste wood into value-added building materials in line with circular economy goals.