Abstract

Tall timber buildings are increasingly promoted as a low-carbon alternative to conventional construction systems; however, consistent quantitative data on the material intensity (MI) of mass timber products across new building typologies remain limited. Estimating MI is essential to improve understanding of material use in timber construction and to support assessments of environmental impacts and potential benefits. This study quantifies the material intensity of mass timber products in contemporary tall timber buildings using a statistically representative global sample. The novelty of the work lies in the aggregation of plan-based material quantities across multiple regions, building uses, and structural systems, enabling systematic cross-project comparison beyond single case studies. A representative sample of 56 projects was selected from a worldwide dataset of 301 tall timber buildings, stratified by continent, building use, and structural system. Material intensity was estimated for representative floor sections using architectural drawings, construction details, and project specifications, excluding non-structural elements. The results indicate an average MI of 132.8 kg/m2 for mass timber products (e.g., CLT or GLT, not equivalent to solid wood mass). Hybrid buildings exhibit lower timber MI values (123.0 kg/m2) than timber-only structures (173.3 kg/m2), while panel-based systems show higher MI than postbased configurations. These findings provide a first-order benchmark for material use in tall timber buildings and highlight their potential contribution to sustainable urban development through the substitution of carbon-intensive materials, while acknowledging methodological limitations related to reliance on project documentation and variability in product composition.