Environmental impacts of structural and concrete formwork plywood in Japan
摘要
Addressing climate change requires reducing greenhouse gas (GHG) emissions across industries. Plywood, a wood-based material, has the potential to be a carbon–neutral product if sourced from sustainably managed forests. However, fossil fuel resources are used at various stages of production, leading to GHG emissions. This study evaluates the environmental impacts of plywood manufacturing in Japan, focusing on structural and concrete formwork plywood, using life cycle assessment (LCA). Data were collected from 18 plywood factories across Japan, covering 64% of structural plywood and 94% of concrete formwork plywood production in the country. Both mass and economic allocation methods were applied. The results showed that structural plywood had GHG emissions of 166 kg-CO₂eq/m3 under mass allocation and 185 kg-CO₂eq/m3 under economic allocation. For concrete formwork plywood, GHG emissions were 205 kg-CO₂eq/m3 and 229 kg-CO₂eq/m3, respectively. Key contributors to emissions include electricity consumption and adhesives, whereas coatings play a significant role in concrete formwork plywood production. All the surveyed factories used biomass boilers, primarily fueled by in-house wood residue. Factories with on-site biomass power generation had lower GHG emissions owing to their reduced reliance on purchased electricity. The analysis also highlighted that optimizing the paints used in concrete formwork plywood production could significantly reduce environmental impacts. Furthermore, while biogenic carbon absorption and emissions are much greater than fossil fuel-derived emissions, ensuring sustainable forestry practices is critical for maintaining carbon neutrality in plywood production. This study provides representative LCA data for Japan’s plywood industry and identifies key areas for emissions reduction. These findings highlight the importance of efficient energy use, alternative low-carbon adhesives and coatings, and roundwood sourcing to minimize the environmental impact of plywood production.