Glossary

Mass Timber Construction

Also known as: Cross-Laminated Timber (CLT), Timber Construction, CLT

A structural building system using large, engineered wood panels and members — most commonly cross-laminated timber (CLT) and glue-laminated timber (glulam) — as an alternative to concrete or steel framing, valued for its comparatively low embodied carbon and speed of erection.

Mass timber sequesters carbon in the wood itself and generally requires substantially less energy-intensive manufacturing than concrete or steel, which has made it a prominent embodied-carbon reduction strategy for developers facing municipal embodied-carbon caps or pursuing aggressive sustainability positioning, particularly in mid-rise office and multifamily construction. Beyond its carbon profile, mass timber panels are prefabricated off-site to close tolerances, which can compress field construction schedules relative to cast-in-place concrete and reduce on-site labor exposure — a scheduling and hard-cost consideration that developers weigh alongside the sustainability narrative. Building code adoption has been the primary constraint on mass timber's growth: revisions to the International Building Code now permit taller mass timber structures in many jurisdictions, but insurers, lenders, and local fire officials have been slower and more variable in their comfort with the material, meaning financing and insurance underwriting for mass timber projects often requires additional technical review relative to conventional construction types.