Wood-frame construction is an important option for school buildings as well as an important choice toward meeting a sustainable future for Ontario. The facts behind this statement are demonstrated by first exploring how wood-frame construction addresses the three major components of sustainable development: what is best for the environment, what is best for the economy, and what is best for society. Factors that owners, funding partners and design teams must consider when developing a project will then be identified, above and beyond sustainability objectives. In practical terms, the impact of building code requirements, geography, and climate on budget and construction scheduling are explored.
Wood construction systems and their components available for use in low-rise school buildings in Ontario are introduced. Site-built and pre-fabricated options, including the innovative cross-laminated timber system, are explained along with the benefits that can be expected from each. The requirements of the Ontario Building Code (OBC) as they pertain to wood construction are elaborated upon.
All references to the Ontario Building Code are based on an extensive review of the OBC as it pertains to wood use in low-rise educational buildings undertaken by code experts Morrison Hershfield for Ontario Wood WORKS! Parts 3, 4 and 5 of the OBC were reviewed to identify pertinent conditions, limitations or restrictions. The report of their analysis is attached in its entirety as Appendix B (page 33).
Unsprinklered one and two-storey school buildings up to 2,400 m2 can be built entirely with wood construction systems, provided certain requirements are met; adding sprinklers to these buildings brings that maximum area up to 4,800 m2 . With the use of firewalls to compartmentalize a larger building into a series of connected smaller buildings, this maximum area can be considerably increased.
A requirement for non-combustible construction does not necessarily imply that school buildings must miss out completely on the benefits of wood construction systems, such as heavy timber roof systems or wood interior elements and finishes. There are also alternative options for complying with OBC requirements which allow for the use of developing wood technologies.
The importance of a wood construction system in terms of benefits to building users and to the environment is explored in detail. Beneficial attributes of wood as a building material include its renewability and its natural ability to capture CO2 from the atmosphere and lock it away in its fibres; that it is sourced from sustainably managed Ontario forests; that manufacturing efficiencies result in a more responsible use of energy and reduced pollutants to the atmosphere when compared with other major building materials; these attributes all help to mitigate climate change.
The benefits of a wood construction system during the construction phase, in terms of material delivery times and optimized construction scheduling are also explored, along with benefits during the life of the building. Some of these benefits are a result of wood’s natural thermal and acoustical properties; others, such as durability and adaptability, result from wood’s natural properties combined with the correct use of the products. There are also less quantifiable though equally important effects, such as the warmth of a natural system and its impact on the learning environment. Five case studies, four schools across the country, and one in the United States, are included to help demonstrate these benefits.
