One Floor at a Time: Cross-Laminating a Sustainable Future for Mass Timber in North America

Abstract

Cross-Laminated Timber (CLT) started in Germany and Austria in the early 1990s. As old-growth timber became difficult to find, glue-laminated timber (Glulam) and other engineered products became popular.Since the advent of Mass Timber products around the world, architects, engineers, and manufacturers have leveraged CLT and other Mass Timber products for their advantages, including design flexibility, aesthetics, strength to weight ratio, and overall material performance. There is a revolution in the building sector that is working to elevate timber to the level of steel and concrete, mostly through taller and longer spanning structures.In addition to many aesthetic and structural performance opportunities, and as a renewable resource with low embodied energy, CLT offers a low carbon footprint while also sequestering and serving as a carbon sink. Interest in CLT as a new engineered wood product in North America is still in the early stages of development and is widely and rapidly proliferating. Demand for CLT in the USA and Canada is driven by architects and engineers requiring sustainable timber-based building products and systems (Mohammad et al., Wood Design Focus 22:3–12, 2012). While the classic wood frame construction is a sound and economical option for smaller residential construction, CLT provides an opportunity for the North American wood industry to build both larger and taller structures in wood. However, development is delayed by building regulations that cautiously safeguard the public health, safety, and welfare whenever a novel building product is introduced, materiality notwithstanding. This chapter is intended to advance the knowledge of Cross Laminated Timber technology. In addition, it will examine trends in mass timber construction in North America from the perspective of carbon footprint, structural performance, fire, and life safety. To that end, we are describing a legacy of excellence of Mass Timber construction in sustainability and tall building design and construction.This chapter consists of: Introduction: Rings of time. Availability and abundance: A naturally warm resource. CLT, NLT, DLT, GLT, MPP, LVL: Ingredients in the alphabet soup for the mass timber soul. Organic paths of resistance: Structural strength, directionality and grain. Sustainability and Performance: Time and time again: A most renewable natural resource. The trees they do grow high: Innovation and the promise of technology in tall timber buildings … and the leaves they do grow green: Embodied energy, sustainability and green building. One tree at a time: Carbon footprint, carbon sequestration, and finding the forest through the trees (FFTT). Case Studies Conclusion Cross laminated timber: Leading the way into a sustainable future for mass timber. References KeywordsRings of timeTimber and timeForest through the treesTimber buildingsMass timber constructionCross-laminated timberTimber reuseLife cycle assessment of mass timberRecycling and demolitionBullitt CenterBrock CommonsT3 MinneapolisJohn W Olver Design BuildingPrefabrication