When Adidas announced plans for a two-building expansion of their North American headquarters, speed and budget were key criteria. They wanted a campus that reflected their culture and commitment to quality, authenticity and innovation, but had a strict 24-month deadline. In response, the design and construction team chose a hybrid of precast concrete and mass timber for one building, and a mass timber post-and-beam solution for the other, using prefabrication to reduce the construction schedule by more than three months.
Buildings constructed for the U.S. Department of Defense (DoD) often have to meet blast-resistance requirements to mitigate the potential effects of terrorism. Terrorism is also a growing threat for civilian buildings (e.g., iconic structures, corporate headquarters, etc.), necessitating more building designers to incorporate blast resistance into their designs. The emergence of mass timber construction, and cross-laminated timber (CLT) in particular, offers a sustainable building material alternative that can also meet blast-resistance criteria in many circumstances.
The report describes a new structural system in wood that is the first significant challenger to concrete and steel structures since their inception in tall building design more than a century ago. The introduction of these ideas is fundamentally driven by the need to find safe, carbon-neutral and sustainable alternatives to the incumbent structural materials of the urban world. The market for these ideas is quite simply enormous. The proposed solutions have significant capacity to revolutionize the building industry to address the major challenges of climate change, urbanization, sustainable development and world housing needs.
Aptly named for its goal of inspiring new ways to build, Catalyst is the first cross-laminated timber (CLT) office building constructed in Washington state. It is also designed to Passive House principles and to achieve zero-carbon and zero-energy certification from the International Living Future Institute (ILFI), making it a leading example of sustainable building design.
An overview on the mechanical and physical properties of cross laminated timber (solid wood
panels) in the building industry and its use in timber construction is presented. Structure-property
relations for solid wood based materials are discussed. Important properties, such as strength, sorption, diffusion, thermal conductivity in relation to the board structure are presented. By varying the structure, the properties can be optimized over a wide range. The focus of this publication lies on experimental works performed by Swiss researchers at the ETH Zürich.
Project contact is Frank Lam at the University of British Columbia
A continuous CLT floor/roof system that has two way bending action across multiple CLT panels will create open floor space with long spans in both major and minor directions, making mass timber construction more competitive and cost-effective. A design guide on CLT two way floor/roof system, incorporating the results from the two phases of study, will be developed at the end.
Bridge inspection using a drone, also referred to as an unpiloted aircraft system, has gained more interest in recent years among bridge owners, researchers, and stakeholders because of its efficiency and effectiveness. In fact, numerous bridges classified as structurally deficient in the United States that require more attention and effort for maintenance activities can be inspected using drones in an efficient manner. The primary goal of this project was to evaluate drones as supplemental bridge inspection tools for bridges that present accessibility challenges for inspectors. To accomplish this goal, an extensive literature review and technical survey were initially conducted to gain knowledge of the state-of-the-art and practices and critical considerations that should be accounted for while conducting inspections. Also, analysis of the drones was conducted and the most suitable drone for bridge inspections was selected. To recognize the drone-enabled inspection efficiency, preliminary inspections were conducted for structural damage identification in three structures, including a reinforced masonry building and two pedestrian timber deck bridges. With the knowledge and techniques established during the preliminary inspections, a six-stage recommended bridge inspection protocol using the drone was proposed and applied to two in-service highway timber bridges, including a timber arch bridge and a three-span timber girder bridge in South Dakota. Through the acquisition and analysis of image and video data, the effectiveness of the drone platform was evaluated in terms of image quality, damage identification and quantification, and comparisons with results from traditional inspections conducted on the bridges. This study details drone-enabled inspection advantages and challenges and provides conclusions and recommendations for future work. A key finding demonstrated throughout this project was that different types of structural damage on the bridges were efficiently identified using the drone.
Interior partition walls for non-residential and high-rise residential construction are an US$8 billion market opportunity in Canada and the United States (Crespell and Poon, 2014). They represent 1.6 billion ft² (150 million m²) of wall area where wood currently has less than 10% market share. To approach this market a new system would be needed to compete against the incumbent system (wood/steel stud plus gypsum). The system would need to have an installed cost before finishing of approximately US$5 per ft² or lower. The system would also need to meet several code requirements for strength, sound transmission and fire resistance (flame spread and burn through). Crespell and Poon further concluded that to be truly transformative, the system would also need to address major trends impacting the building industry including reducing labor, reducing skilled labor, reducing onsite waste, reducing call-backs, and easily recyclable with low environmental impact. A likely market entry point for wood-based interior partition systems may be in taller and larger wood buildings.
Work described in this report investigated the fabrication, installation, acoustic and combustion properties of prototype interior partition wall designs.
Two types of non-structural prototype interior wall panels designated Type A and Type C were installed between two offices in the FPInnovations Vancouver laboratory. Wood sill plates for mounting the prototype panels were fastened to the concrete floor, sides and top of the opening between the two offices to produce a frame for mounting the test panels. Panels were fastened to the frame using dry wall screws. This same method of installation is envisioned in practice. The installation method makes it easy and fast to both install and remove the wall panels.
Acoustic tests showed the difference in ASTC rating measured between a double wall composed of Type A and Type C prototype panels compared with a double wood stud wall with gypsum board faces was approximately 6 ASTC points. A 6 point difference would be clearly noticeable. Although the results of this study are largely qualitative, they suggest that the prototype interior partition panels would have an acoustic advantage compared to stud wall designs.
In a related study summarized in this report, the combustion properties of three prototype interior panel constructions, including Types A and C evaluated in this report, indicated that any of the three types of partition constructions could be used in combustible construction in accordance with Division B of the National Building Code of Canada.
A second related study, also summarized in this report, estimated an installed cost of US$4.07 per ft² including overhead and profit for unfinished panel partitions comparable to panel construction Type C (gypsum/OSB/wood fibre insulation) as evaluated in this study. Thus, there would appear to be potential installed and finished cost advantages for the wood-based panel partitions compared to steel or wood stud walls with gypsum faces.
Other potential advantages of the prototype interior partition panels compared with the most common, currently-used systems (wood/steel stud plus gypsum) include ease and speed of installation, ease and speed of removal, design flexibility, prefabrication including pre-finishing, and easy installation of services.
Based on the positive results of these exploratory studies, further development of wood-based interior partition systems including design, fabrication, installation and in-service performance would appear justified. Knowledge of the products and testing methods developed in these studies would be expected to speed further development.
This volume presents a history of heavy timber construction (HTC) in the United States, chronicling nearly two centuries of building history, from inception to a detailed evaluation of one of the best surviving examples of the type, with an emphasis on fire resistance. The book does not limit itself in scope to serving only as a common history. Rather, it provides critical analysis of HTC in terms of construction methods, design, technical specifications, and historical performance under fire conditions. As such, this book provides readers with a truly comprehensive understanding and exploration of heavy timber construction in the United States and its performance under fire conditions.
While taller mass timber buildings continue to capture worldwide attention, the University of Idaho chose to pursue a different type of innovation with the Idaho Central Credit Union Arena by showcasing wood’s impressive long-span capabilities. Inspired by the rolling hills of the nearby Palouse, the undulating wood roof of this sports and events facility soars over the open space below, creating a visually stunning structure not typically associated with large arenas.
This project is also unique in that it was built through a collaboration of Idaho stakeholders, using wood harvested from the University of Idaho’s Experimental Forest, made into glue-laminated timber (glulam) beams by Idaho manufacturers. “The complex structure makes a strong statement, not only for what mass timber can do, but also for what Idaho’s timber industry can do,” said Lucas Epp, Vice President and Head of Engineering for StructureCraft.