Surface Flammability and Flame-Spread Ratings
The rate at which flame spreads on the exposed interior surfaces or a room or space can have an impact on the rate of fire growth within an area, especially if the materials of the exposed surfaces are highly flammable. Therefore, the National Building Code of Canada (NBC)¹ regulates the surface flammability of any material that forms part of the interior surface of walls, ceilings and, in some cases, floors, in buildings. Based on a standard fire-test method, the NBC uses a rating system to quantify surface flammability that allows comparison of one material to another, and the ratings within that system are called flame-spread ratings (FSR). For some buildings, the smoke generated by materials or products lining some areas of the building when they burn is also regulated by the NBC. Since it may take some additional time for occupants to exit the building, this applies to all unsprinklered high buildings and all elevators or Group B occupancies in high buildings. The FSR and SDC is also regulated for some materials used in ducts and plenums. The smoke produced from a material or product is measured and quantified through another rating system, based on a standard fire-test method — the smoke developed classification (SDC). For most wood products used as interior finishes, both of these properties — the FSR and the SDC — are to be determined in accordance with CAN/ULC-S102, “Standard Method of Test for Surface Burning Characteristics of Building Materials and Assemblies.”² For flooring, CAN/ULC-S102.2 “Standard Method of Test for Surface Burning Characteristics of Flooring, Floor Coverings, and Miscellaneous Materials and Assemblies is to be used when a SDC or FSR is required.
Fire Separations & Fire-Resistance Ratings
Fire separations and fire-resistance ratings are often required together but they are not interchangeable terms, nor are they necessarily mutually inclusive. The National Building Code of Canada (NBC)1 provides the following definitions: A fire separation is defined as “a construction assembly that acts as a barrier against the spread of fire.” A fire-resistance rating is defined as “the time in minutes or hours that a material or assembly of materials will withstand the passage of flame and the transmission of heat when exposed to fire under specified conditions of test and performance criteria, or as determined by extension or interpretation of information derived therefrom as prescribed in [the NBC].” In many buildings, the structural members such as beams and columns, and structural or non-structural assemblies such as walls and floors, are required to exhibit some degree of resistance to fire in order to prevent the spread of fire and smoke, and/or to minimize the risk of collapse of the building in the event of a fire. However, fire separations are assemblies that may or may not be required to have a specific fire-resistance rating, while structural members such as beams and columns that require a fire resistance rating to maintain the structural stability of a building in the event of a fire are not fire separations because they do not “act as a barrier against the spread of fire.” Requirements for fire separations and fire-resistance ratings are just one aspect of the fire-safe design approach used by the Code to reduce risk to building occupants of injury, as well as to reduce risk of property loss. Together, they are key elements to the strategy of controlling fire spread called “compartmentation.”
Tall Wood Course of Construction Site Fire Safety
The vulnerability of any building, regardless of the material used, in a fire situation is higher during the construction phase when compared to the susceptibility of the building after it has been completed and occupied. This is because the risks and hazards found on a construction site differ both in nature and potential impact from those in a completed building; and these risks are occurring at a time when the fire prevention elements that are designed to be part of the completed building are not yet in place. For these reasons, construction site fire safety includes some unique challenges. Developing an understanding of these hazards and their potential risks is the first step towards fire prevention and mitigation during the course of construction (CoC).
Four-Storey Wood School Design in British Columbia: Life Cycle Analysis Comparisons
Climate change is one of the largest threats facing the planet today. The construction industry accounts for 11% of global carbon emissions, playing a significant part in the climate crisis. To determine the best solution for future school buildings, not only does practicability, economy and constructability play a part, so does sustainability. In order to better understand the embodied carbon emissions associated with the construction of new school buildings in British Columbia, the embodied carbon content associated with the four framing systems examples in the companion report, An Analysis of Structural System Cost Comparisons (costing study), was assessed. The purpose of this study is to allow the embodied carbon associated with these systems to become an important factor when choosing a viable scheme. Embodied carbon is the carbon footprint of a material or product. To determine the embodied carbon of a building you must consider the quantity of greenhouse gases associated with the building. The most effective way to measure this is through Life Cycle Analysis (LCA), a study which determines the embodied carbon from cradle to grave (material extraction to building demolition). Consequently, an LCA was conducted for each of the four schemes presented in the costing study. Additionally, for wood frame Options A and B, WoodWorks online carbon calculator was used to determine the potential carbon savings associated with carbon sequestering.
Four-Storey Wood School Design in British Columbia: An Analysis of Structural System Cost Comparisons
As land values continue to rise, particularly in higher-density urban environments, schools with smaller footprints will become increasingly necessary to satisfy enrollment demands. There are currently several planned new school projects throughout British Columbia that anticipate requiring either three-or four storey buildings, and it is forecast that demand for school buildings of this size will continue to rise. Though timber construction would offer a viable structural material option for these buildings, the British Columbia Building Code (BCBC 2018) currently limits schools comprised of timber construction to a maximum of two storeys, while also imposing limits on the overall floor area. Given these constraints, the development of viable structural options that would accommodate larger and taller schools constructed primarily with timber materials has not been a key focus. With the above factors in mind, the purpose of this report is to build upon the findings of the previously published Design Options for Three- and Four-Storey Wood School Buildings in British Columbia prepared by Fast + Epp and Thinkspace dated November 2019. Specifically, this report supplements the previous one by providing guidance in assessing and comparing the various framing options considered in the previous report primarily on a cost basis.
Wood Design Manual 2020
The Wood Design Manual is the Canadian reference on the design of timber structures, under gravity and lateral loadings, according to Part 4 of the National Building Code of Canada (NBC) and the “Engineering design in wood” standard (CSA O86). It provides guidance and design examples on sawn and engineered wood members, their connections and fire design. The most common design situations encountered by practicing engineers are covered through intuitive Selection Tables. In addition, the Wood Design Manual contains the latest CSA O86 Standard, as well as a technical commentary written by timber design experts including members of the Standard’s technical committee. The 2020 Wood Design Manual includes a copy of the CSA O86:19 Standard, incorporating Update No.3 – July 2021. The main changes in this edition are:
Canadian Span Book 2020
This new edition of The Span Book includes added tables for deck joists and beams, more lintel options, and recalculates all spans using revised shear properties.
Design Options for Three- and Four Storey Wood School Buildings in British Columbia
As land values continue to rise, particularly in higher-density urban environments, schools with smaller footprints will become increasingly more necessary to satisfy enrollment demands. There are currently a number of planned new school projects throughout British Columbia that anticipate requiring either three-or four-storey buildings, and it is forecasted that the demand for school buildings of this size will continue to rise. Though timber construction would offer a viable structural material option for these buildings, the British Columbia Building Code (BCBC 2018) currently limits schools comprised of timber construction to a maximum of two storeys, while also imposing limits on the overall floor area. Given these constraints, to date there has not been much effort put into the development of viable structural options that would accommodate larger and taller schools constructed primarily with timber materials. With the above factors in mind, the purpose of this study is to illustrate the range of possible timber construction approaches for school buildings that are up to four storeys in height. Given this emphasis on four-storey construction, this study focuses on the main classroom blocks within a school building, as these portions of the building are the ones that are the most likely to take advantage of an increased number of storeys. While other portions of school buildings, such as gymnasiums, shops, and multi-purpose areas are also strong candidates for wood construction systems, since there are already numerous examples of this type of construction these areas are not emphasized in this report.
Shane Homes YMCA At Rocky Ridge CALGARY, AB
Calgary’s aspirations to become a world-class city are supported by its recent investments in infrastructure and architecture, including the $192-million Shane Homes YMCA at Rocky Ridge, which was bolstered by the largest private donation ever contributed to the local YMCA. Shane Homes is a Calgary-based development company, established in 1979, that contributed $3.5 million for the project. This is the first recreational facility for the northwest corner of the city, serving a community of more than 100,000 residents. Nestled in Calgary’s rolling foothills, the curvilinear design of the Shane Homes YMCA at Rocky Ridge is inspired by the surrounding landscape. The building is sited within a natural park featuring reconstructed wetlands. Multiple pathways and a timber pedestrian bridge curve throughout the site, linking to the regional pathway system. Glulam timber is the primary structural component, allowing for a geometrically complex design at considerably less cost than other materials. The dramatic silhouette is dened by the largest freeform timber roof structure in North America. Construction began in 2014, and since opening to the public in January 2018, this new recreation centre has become a bustling hub of sport and activity. The Shane Homes YMCA has won numerous awards, including a 2019 Wood WORKS! Prairie Wood Design Award, a 2018 Canadian Wood Council Award and a 2017 CanBIM Best in BIM Award.
The Span Book 2009
Mid-Rise Best Practice Guide Proven Construction Techniques for Five-and Six-Storey Wood-Frame Buildings
When the provincial government changed the British Columbia Building Code (BCBC) in 2009 by increasing the permissible height for wood-frame construction from four storeys to six for residential buildings, it joined many other jurisdictions around the world in recognizing the role that wood construction should play in the creation of a sustainable, built environment. Scientific evidence and independent research had shown that such buildings could meet the performance requirements of the BCBC in regard to structural integrity, fire safety, and life safety. That evidence has now also contributed to the addition of new prescriptive provisions for wood construction, as well as paved the way for future changes that will include more permissible uses and ultimately greater permissible heights. As a result of this research, and the successful implementation of many mid-rise wood-frame residential buildings in BC, the Canadian Commission on Building and Fire Codes approved similar changes to the National Model Construction Codes. The 2015 edition of the National Building Code of Canada (NBC) now permits the construction of six-storey residential, business, and personal services buildings using traditional combustible construction materials. The changes to Part 3 of the NBC, which are being considered for adoption by British Columbia in late 2018, address the objectives of safety, fire, and structural protection of buildings. With more than 100 five- and six-storey woodframe buildings completed in BC since 2009, and many others either designed or under construction, there is clear market confidence in this new type of building. This construction supports the goals of many municipalities: to find affordable and sustainable ways to accommodate their growing populations, as well as create more complete and resilient communities. With each completed building, architects, engineers, builders, and developers have added to their knowledge base and refined their best practices for mid-rise wood-frame construction. The five projects featured in this publication are representative of the diverse and varied application of these techniques to different geographic and market conditions, from small towns to dense urban centres and from affordable rental accommodation to high-end condominiums.
Introduction to Wood Design 2018
Introduction to Wood Design has been prepared to facilitate and encourage the instruction of wood engineering at Canadian universities and colleges. The publication is a supplement to the Wood Design Manual 2017.
