Bamboo construction materials: Carbon storage and potential to reduce associated CO2 emissions.

The construction industry is one of the largest contributors of CO2 emissions. To achieve the goal of carbon peaking by 2030 and carbon neutrality by 2060, China needs to develop carbon reduction pathways for the construction industry. Bamboo is believed to be one of the most appropriate candidates for afforestation to reduce CO2 concentration and alleviate the effects of climate change. It is also an ideal building material with high tensile and compressive strengths. However, the carbon emissions and storage of bamboo building materials have not been well understood. This study aims to quantify the CO2 emissions and carbon storage of bamboo building materials and to analyse the potential to reduce these carbon emissions. Results show that the planting phase contributes the largest amount of carbon uptake whilst the production phase contributes the largest amount of carbon emissions. 'Carbonisation' is found to be the production process with the highest carbon emissions, followed by 'antimould, anticorrosion and drying treatment' and 'glue application'. Three strategies that are useful in reducing carbon emissions are proposed and validated. After the implementation of the proposed strategies, the average and median amount of carbon emissions changed from 1291.63 and 1290.75 kg to 1088.36 and 1090.29 kg. Taking all phases into account, one cubic meter of bamboo assembled components can reduce 249.92 kg CO2 from the atmosphere. Compared to dimensioned lumber, engineered lumber, cement, steel, timber, hempcrete, bamboo building materials have the highest CO2 emissions and carbon storage. The carbon storage of bamboo assembled components per tonne is around 140 kg more than that of timber per tonne. This study is expected to assist not only researchers in understanding the carbon reduction potential of bamboo building materials but also practitioners in promoting bamboo building-based carbon reduction pathways.