Durability and protection of mass timber structures: A review

Mass timber (MT), a group of large engineered structural wooden panels such as cross-laminated timber (CLT), glue-laminated timber (Glulam), laminated veneer lumber (LVL), etc., is becoming increasingly popular due to sustainable construction. Despite the numerous benefits of MT-based buildings, such as low-carbon emission, short construction time, and cost-effectiveness, the concerns regarding the durability of MT may limit their market acceptance. In this review, we discuss the advantages and opportunities of applying MT in tall buildings, as well as the durability issues associated with MT application. We examine the traditional wood protection techniques including, preservative treatment, thermal and chemical modification, and discuss the potential of applying these techniques for MT protection. We survey the recent studies on MT durability evaluation, as well as the recent progress in MT structure protection through a moisture control strategy. Finally, we highlight the MT protection strategies through the preservative, thermal, and chemical treatment approaches, review the effects of these treatment methods on the properties of MT such as wettability, glue penetration, bonding strength, etc., and discuss the future of the field.