The growing timber manufacturing industry faces challenges due to increasing geometric complexity of architectural designs. Complex and structurally efficient curved geometries are nowadays easily designed but still involve intensive manufacturing and excessive machining. We propose an efficient form-giving mechanism for large-scale curved mass timber by using bilayered wood structures capable of self-shaping by moisture content changes. The challenge lies in the requirement of profound material knowledge for analysis and prediction of the deformation in function of setup and boundary conditions. Using time- and moisture-dependent mechanical simulations, we demonstrate the contributions of different wood-specific deformation mechanisms on the self-shaping of large-scale elements. Our results outline how to address problems such as shape prediction, sharp moisture gradients, and natural variability in material parameters in light of an efficient industrial manufacturing.
Cross-Laminated Timber (CLT) is an innovative structural system based on the use of large-format, multilayered panels made from solid wood boards glued together, and layers at 90 degrees. This cross-laminated configuration translates into panels that are monolithic, stable, and experience minor shrinkage, which allows them to be used for the most diverse building applications, such as walls, floors and roofs. Developed in the early 1990 in Switzerland, as a way to reduce waste in sawmills, the system has been successful in Europe for the past 20 years, and more recently has made inroads into the Australian and North America markets. In the United States, the adoption of the system is still in its early stages. Recent research has shown that CLT could be cost-competitive as an alternative to concrete structures and for buildings over 6 stories high. The main goal of this study was to understand the market impediments to widespread adoption in the U.S. from an architecture firm’s point of view and compare the economic performance of CLT with that of traditional constructions systems, namely concrete and steel. A performing arts facility on the west coast of the US was evaluated as a case study. In order to accomplish this goal, a series of interviews with building professionals, as well as meetings with construction and estimating firms were conducted. Then an in depth analysis was performed to evaluate and compare the economic performance of the different construction systems in terms of cost of materials, labor, and speed of construction. This research addresses some of the key questions that must be answered if we are to understand the viability of a CLT market in the U.S.
This paper presents a new approach to robotic fabrication in the building industry through the conceptualization, development and evaluation of a largescale, transportable and flexible robotic timber construction platform – named TIM. Novel solutions are necessary to make robotic fabrication technologies more accessible for timber construction companies. The developed robotic system is location independent and reconfigurable. It can be rapidly integrated into existing fabrication environments of typical carpentries on a per-project basis. This allows the exploitation of emerging synergies between conventional craft and specialized automation technologies and benefits both quality and productivity of the trade. We portrait how the platform enabled the effective robotic prefabrication of a complex segmented wood shell structure and discuss the fabrication system based on critical performance parameters. Further research is needed to disentangle the mutual dependencies of building-systems and respective automation technologies.
The choice of materials may play an important role in achieving the common European aims of near zero energy demand and greenhouse gas (GHG) emissions in the lifecycle of buildings. The production of timber materials demands lower emissions than concrete and steel. To guide political and industrial priorities, it is vital to estimate the emission effects of increased use of timber.
The article reports on a broad study that had the following aims:
1. To forecast the number, types, floor area, and location of new buildings that will be built in Oslo and Akershus counties between 2015 and 2030.
2. To estimate how many of these new buildings (a) will be and (b) could be built with timber as the main construction material.
3. To compare these timber potentials to the present and future availability of nationally and sustainably sourced and manufactured timber.
4. To estimate the effect on GHG emissions when substituting concrete and steel with timber in the production of new buildings in Oslo and Akershus counties between 2015 and 2030.
The research is based on official prognoses for population growth. They are combined with building predictions derived from municipal statistics and plans. A GHG reduction factor is extracted from existing studies of the effects of conversion to timber. This factor is used to estimate the GHG saving potentials of different scenarios for timber use.
These Joint Professional Practice Guidelines – Encapsulated Mass Timber Construction Up to 12 Storeys were jointly prepared by the Architectural Institute of British Columbia (AIBC) and Engineers and Geoscientists British Columbia.
The AIBC and Engineers and Geoscientists BC regulate and govern the professions of architecture, engineering, and geoscience under the Architects Act and the Professional Governance Act. The AIBC and Engineers and Geoscientists BC each have a regulatory mandate to protect the public interest, which is met in part by setting and maintaining appropriate academic, experience, and professional practice standards.
Engineering Professionals are required per Section 7.3.1 of the Bylaws - Professional Governance Act to have regard for applicable standards, policies, plans, and practices established by the government or by Engineers and Geoscientists BC, including professional practice guidelines. For Engineering Professionals, these professional practice guidelines clarify the expectations for professional practice, conduct, and competence when providing engineering services for EMTC buildings. For Architects, these guidelines provide important information and identify issues to be considered when providing architectural services for EMTC buildings. These guidelines deal with the performance of specific activities in a manner such that Architects and Engineering Professionals can meet their professional obligations under the Architects Act and the Professional Governance Act.
These guidelines were developed in response to new classifications of building size and construction relative to occupancy introduced in the 2018 British Columbia Building Code (BCBC), under Division B, Article 18.104.22.168EMTC. Group C, up to 12 storeys, Sprinklered, and Article 22.214.171.124EMTC. Group D, up to 12 storeys, Sprinklered. These new classifications were introduced in Revision 2 of the 2018 BCBC on December 12, 2019 and in Amendment 12715 of the 2019 Vancouver Building By-law (VBBL) on July 1, 2020. Additionally, provisions related to Encapsulated Mass Timber Construction (EMTC) were introduced in Revision 1 of the 2018 British Columbia Fire Code (BCFC) on December 12, 2019.
These guidelines were first published in 2021 to provide guidance on architectural and engineering considerations relating to these significant changes to the 2018 BCBC, the 2019 VBBL, and the 2018 BCFC. For Engineering Professionals, these guidelines are intended to clarify the expectations of professional practice, conduct, and competence when Engineering Professionals are engaged on an EMTC building. For Architects, these guidelines inform and support relevant competency standards of practice to be met when Architects are engaged on an EMTC building.
As with all building and construction types, the EMTC-specific code provisions prescribe minimum requirements that must be met. The majority of EMTC of 7 to 12 storeys are considered High Buildings, and as such are subject to the BCBC, Subsection 3.2.6. Additional Requirements for High Buildings.
This research project presents both innovative multi-scalar modelling methods and production processes aimed at facilitating the design and fabrication of free-form glue-laminated timber structures. The paper reports on a research effort that aims to elucidate and formalize the connection between material performance, multi-scalar modelling (Weinan 2011), and early-stage architectural design, in the context of free-form glue-laminated timber structures. This paper will examine how the concept of multi-scalar modelling as found in other disciplines can also be used to embed low-level material performance of glue-laminated timber into early-stage architectural design processes, thus creating opportunities for feedback across the design chain and an increased flexibility in effecting changes. The research uses physical prototypes as a means to explore and evaluate the methods presented.