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Climate change, environmental degradation, and limited resources are motivations for sustainable forest management. Forests, the most abundant renewable resource on earth, used to make a wide variety of forest-based products for human consumption. To provide a scientific measure of a product’s sustainability and environmental performance, the life cycle assessment (LCA) method is used. This article provides a comprehensive review of environmental performances of forest-based products including traditional building products, emerging (mass-timber) building products and nanomaterials using attributional LCA. Across the supply chain, the product manufacturing life-cycle stage tends to have the largest environmental impacts. However, forest management activities and logistics tend to have the greatest economic impact. In addition, environmental trade-offs exist when regulating emissions as indicated by the latest traditional wood building product LCAs. Interpretation of these LCA results can guide new product development using biomaterials, future (mass) building systems and policy-making on mitigating climate change. Key challenges include handling of uncertainties in the supply chain and complex interactions of environment, material conversion, resource use for product production and quantifying the emissions released.

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.

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