Circular bioeconomy in the Global South: The case of circular bio-based building material use in Vietnam.

Circular bio-based building materials (CBBMs) offer a sustainable solution for reducing the climate impact of buildings and are crucial for transitioning the construction industry towards a circular economy (CE). Reusing, cascading, and recycling municipal biowaste, agricultural by-products, and residues to produce CBBMs can optimise resource utilisation and deliver substantial environmental, economic, and social benefits, as well as promote a circular bioeconomy (CBE). Despite these benefits, the CBBM adoption in the Global South remains limited due to various barriers. Notably, the existing literature lacks research into the current use status and adoption barriers of CBBMs in these regions. This study addresses these gaps by investigating the usage and barriers to CBBM adoption, based on insights from building professionals in Vietnam. Data from 123 valid responses were analysed using descriptive statistics, ranking analysis, and exploratory factor analysis. The findings indicate that "circular bio-based panels or particle boards", "agricultural by-products mixed with clay for wall construction", and "circular bio-based concrete, bricks, fillers, or binders" are the most commonly utilised CBBMs. Government-related barriers, such as "building code restrictions and lack of regulation", "lack of government promotion and incentives", and "lack of design guides and tools for projects using CBBMs", are identified as the most significant obstacles to CBBM uptake. Kendall's W and Whitney U tests reveal a strong consensus among experts, with no significant differences between those with and without firsthand CBBM experience regarding their ranks of barriers. Exploratory factor analysis identified 20 independent barriers, grouped into four components, with the one containing cost and time-related barriers emerging as the most dominant to market and technical-related, government-related, and information and perception-related barriers. The study's findings could provide useful insights for policy recommendations to promote CBBM adoption in Vietnam. These insights may also inform strategies in other Global South countries with similar socioeconomic conditions to facilitate the transition to CE and CBE, mitigating climate change impact, and promoting sustainable development.