One of the major motivations for using mass timber is the ease of facilitating off-site construction. However, the off-site construction industry has difficulties in attracting interest in the construction ecosystem. Based on a study on mass wood construction motivations and barriers, this sub-project will examine the construction value chain to identify the barriers and incentives. The project outcome will be strategies that would be recommended to the wood industry to mitigate barriers and promote the incentives, thereby leading to more adoption of off-site construction for mass timber structures.

One of the major motivations for using mass timber is the ease of facilitating off-site construction. However, the off-site construction industry has difficulties in attracting interest in the construction ecosystem. Based on a study on mass wood construction motivations and barriers, this sub-project will examine the construction value chain to identify the barriers and incentives. The project outcome will be strategies that would be recommended to the wood industry to mitigate barriers and promote the incentives, thereby leading to more adoption of off-site construction for mass timber structures.

Recently some overseas jurisdictions have established policies and guidelines to enhance deployment of best practices to reduce waste and energy use in the construction sector that are aligned with circular economy principles (Mangialardo and Micelli 2019). This sub-project will focus on off-site wood construction projects in rural and urban areas, and attempt to optimize the value chain according to a circular economy approach by considering material selection, prefabricated components, and CO2 emissions related to material production and transportation. The outcome will be a mathematical model that can be used by builders and designers to select building materials and their suppliers, and design a material management process for a specific construction project that meets the circular economy principles. Project T4-2 Enhancing the Green Credential of Wood Construction This project consists of 4 sub-projects to develop information that will further substantiate the life cycle environmental benefits of wood construction, by accounting for factors that have not been properly considered in previous work.

Acoustic insulation is a major serviceability consideration for wood buildings. The use of LCA for evaluating and confirming the benefits of wood buildings has been well documented. A unique feature of Next Generation Wood Construction Page 17 of 34 Chui, Y. H. (18138) this sub-project is to integrate LCA in the acoustic design of wood building assemblies by considering their acoustic performance and its impact on the psychological well-being of its occupants, with a key outcome being an acoustic design procedure incorporating LCA principles. A key benefit of the developed procedure is to ensure that there is no problem shift from one environmental impact category to another and to ensure that the proposed construction system is optimized in terms of its acoustic and overall LCA performance. This sub-project will collaborate with sub-project T1-4-B.

The Canadian forest sector is well integrated between industries (e.g., lumber, composite panels) and has overlapping supply chains. This poses challenges for both attributional and consequential LCA, because many products rely on joint upstream processes and consistent allocation factors are required to appropriately represent the total potential impact of forest activities and their allocation. This sub-project will leverage the most recent physical and economic data and models to provide the LCA community with the tools to address allocation and sectoral changes in a consistent manner.

Performance-based design methodology is being considered for adoption in a future edition of NBCC. The conventional performance-based design method considers technical requirements only, such as structural, fire and energy. Given the environmental benefits of wood and wood construction, it is of interest to integrate the conventional technical design requirements with environmental impact assessment method. The focus of this sub-project will be on off-site or prefabricated wood buildings. Next Generation Wood Construction Page 18 of 34 Chui, Y. H. (18138) The expected outcome will be the development of modern PBD tools that take into consideration the carbon footprints of the building design and the construction process, under natural hazard scenarios, such as earthquakes, hurricanes and snow/ice storms.

Building codes are currently embarking on consultation exercises to determine what future code provisions are necessary to address issues and challenges that will arise as a result of climate change. This sub-project aims to develop future scenarios (or trajectories) of resilient wood building designs, based on trends in building code modernization, in response to climate change and the new emerging certification requirements (e.g., CaGBC’s Zero Carbon Building Program or the Int’l Living Future institute’s Zero Carbon program). The expected outcome will be an analysis tool that allows designers to consider the resiliency of wood buildings when exposed to environmental loads caused by projected future climate change and the life cycle environmental performance.