Overview of Cross-Laminated Timber (CLT) and Timber Structure Standards Across the World

Abstract

 In recent years, Cross-laminated Timber (CLT) has experienced exponential growth internationally, fostering substantial awareness and inter¬est in this renewable construction material. The increasing adoption of CLT in countries and regions of world is resulting in considerable manufacturing investment in engineered wood products more generally. Fabrication of solid timber structural systems using CLT panels requires product standards ensuring strength and stiffness characteristics of the base material in meeting rigorous performance requirements. Given that this nascent technology was only introduced within the last three decades, standards for manufacturing and design are still being developed. Indeed, multiple approaches to standards development have occurred in several regions of the world with little thought to harmonisation. This paper aims to review design standards from throughout the world for CLT and associated timber structures with recommendations towards future development of CLT standardization. For this purpose, an explanation of the general approach used by the following standards relating to CLT and timber codes is presented; Europe: EN-16351, North America: APA/PRG-320, Japan: JAS-3079, International Organization for Standardization (ISO) CLT standard: ISO 16696- 1, Africa: South Africa: SANS-1783/ SANS 10163/ SABS-0163, South America: Brazil: NBR-7190, Oceania: Australia: AS-1720.1, and Asia: China: GB-50005. The current versions of each standard are briefly outlined with the related standard background. For the development of standards in those countries that are yet to adopt a CLT standard, the potential of using other existing standards has been outlined as suggestions. The present review can be a useful resource for researchers, manufacturers, companies, and investors interested in further study of a worldwide harmonized CLT standard.