Impacts of the Allocation Assumption in Life-Cycle Assessments of Wood-Based Panels*

Abstract

Wood processing often involves an array of products and coproducts and a cascade of primary and secondary uses. Prior life-cycle assessment (LCA) reporting allocated environmental burdens to products and coproducts based on mass for multiproduct systems to develop environmental product declarations, which are developed from LCAs following the procedures detailed in product category rules (PCRs). A recent PCR for North American structural and architectural wood products requires allocation by economic value when the main products exceed the value of coproducts by greater than 10 percent. Using recent LCAs of wood-based panels, this article describes the differences in LCA results when using mass and economic allocation methods. For wood panel products that do not use wood residues from primary wood manufacturers (e.g., plywood), an increase in environmental impacts results from an economic allocation approach. For wood panel products made from wood residues (e.g., cellulosic fiberboard), there is a slight decrease in most environmental impact metrics with economic allocation. Sensitivity and variability in LCA results are discussed for the mass and economic allocation approaches.

Citation

Taylor, Adam M.; Bergman, Richard D.; Puettmann, Maureen E.; Alanya-Rosenbaum, Sevda. 2017. Impacts of the allocation assumption in life-cycle assessments of wood-based panels. Forest Products Journal. 67(5-6): 390-396.