High-rise timber buildings: Benchmarks in structural systems, fire safety, prefabrication efficiency and environmental insights of world's 10 tallest completed mass timber projects

This study provides a systematic comparative overview of the world's 10 tallest completed timber buildings, moving beyond descriptive reports to establish a synthesized framework of benchmarks for structural systems, material specifications, fire safety, and environmental performance. It shows that hybrid timber–concrete systems with reinforced concrete (RC) cores dominate current practice, but pioneering timber-dominant solutions, such as glulam trusses and CLT shear walls, signal a gradual shift toward greater structural autonomy. From a material perspective, glulam columns typically range between 0.4 m and 1.0 m and CLT floor panels between 160 and 240 mm, while high-strength glulam grades (GL28–GL32) and C24 CLT emerge as consistent global standards, reflecting the growing maturity of design codes. It also reveals that fire safety in tall timber buildings is achieved through three principal strategies: encapsulation systems, oversized timber structural members with sacrificial charring, and hybrid RC–timber solutions. The tallest timber buildings demonstrate that performance-based validation can achieve two-to-three hour fire ratings, highlighting both the technical feasibility and the regulatory trade-offs of fire-safe timber design. For architects, engineers, and policymakers, the study provides practical reference points that clarify current feasibility, highlight emerging trends, and support the integration of tall timber construction into urban development.