A new, harmonized performance standard for windows, doors and skylights has been developed and will be referenced in the 2010 National Building Code of Canada (NBC), replacing a number of Canadian standards, some of which were outdated. The standard is AAMA/WDMA/CSA 101/I.S.2/A440, NAFS - North American Fenestration Standard/Specification for Windows, Doors, and Skylights.
Revisions to the NBC were recommended by a Canadian Commission on Building and Fire Codes (CCBFC) task group. The task group reviewed the harmonized standard to determine its consistency with the scope and objectives of Parts 5 and 9 of the NBC and its performance levels with respect to currently referenced documents. The resulting proposed changes went to public review in fall 2008 and were subsequently approved by the CCBFC.
In the 2010 NBC, Part 5 will contain a new subsection to ensure consistent application of the requirements and compliance procedures. In Part 9, a single new section on windows, doors and skylights will replace the current sections for doors and windows. Prescriptive requirements have been updated to reflect the harmonized standard, and performance requirements were added, including some for minimum thermal performance targets.
Builders, engineers and consultants will need to learn a new procedure for specifying windows, doors and skylights, as the current A, B, and C rating system used by the 2000 edition of CSA A 440 is being replaced with actual design load and pressure ratings. In addition, performance grades for windows, doors, and skylights will need to be selected according to the CSA's Canadian Supplement (CSA A 440S1, Canadian Supplement to AAMA/WDMA/CSA 101/I.S.2/A 440, NAFS - North American Fenestration Standard/Specification for Windows, Doors, and Skylights), also referenced in the 2010 NBC, to ensure the fenestration products are appropriate for the conditions and geographic location in which they are installed.
The harmonized fenestration standard, substantially different from its predecessors, is supported by industry in both Canada and the United States, as it will help reduce production and marketing costs.
For more information, visit the national codes website at www.nationalcodes.ca or contact Frank Lohmann at 613-993-9599 or frank.lohmann@nrc-cnrc.gc.ca