CSA S520:22

1 Scope 1.1 General This Standard contains best practice guidance for the design and construction of low-rise, wood-frame buildings to withstand high winds corresponding to EF-2 tornado-level wind speeds, assumed to be associated with a reference velocity pressure of 1 kPa. The guidance in this Standard is based on, and written to, supplement the requirements specified in Part 9 of the National Building Code of Canada (NBC) (see Clause 0.4). 1.2 Applicability and limitations The guidance in this Standard has been developed primarily for new wood-frame building construction. The resistance to high wind speeds up to an EF-2 level requires adherence to all provisions and recommendations in this Standard. 1.3 Alterations and additions This Standard can be applied to major alterations and additions to existing buildings where the entire continuous vertical and lateral load path can be upgraded with all primary structural requirements. For alterations and additions to existing buildings where the entire continuous vertical and lateral load path cannot be upgraded, users should start with the non-structural measures provided in Clauses 11through 14. For more information, see Clause 0.3. 1.4 Conflicting requirements In cases where a requirement or method in another standard that is referenced in a regulation conflicts with recommendations in this Standard, the regulatory requirements take precedence. For more information, see Clause 0.5. 1.5 Terminology In this Standard, “shall” is used to express a requirement, i.e., a provision that the user is obliged to satisfy in order to comply with the Standard; “should” is used to express a recommendation or that which is advised but not required; and “may” is used to express an option or that which is permissible within the limits of the Standard. Notes accompanying clauses do not include requirements or alternative requirements; the purpose of a note accompanying a clause is to separate from the text explanatory or informative material. Notes to tables and figures are considered part of the table or figure and may be written as requirements. Annexes are designated normative (mandatory) or informative (non-mandatory) to define their application.