This calculator was originally developed by the Special Interest Group for Dynamic Evaluation of Roofing Systems (SIGDERS) consortia and focused only on wind load determination for roof claddings. This version also determines the wind load of roof claddings and vegetated roof assembly based on the National Building Code of Canada 2020, with the exception of, (1) when the building height is equal to or greater than the smallest dimension of building and, (2) when the building reference height is less than 9 m (30 ft) or the building reference height is greater than 46 m (150 ft). The calculations are performed conservatively by assuming the unit tributary area for various zones of cladding. However, the calculation follows ultimate limit states (ULS) design requirements and uses a principal wind load factor of 1.4 (refer to the National Building Code of Canada 2020, Division B, Table 184.108.40.206.A).
The calculators have been developed and are maintained by the National Research Council of Canada.
The licence agreement must be read and accepted before being able to use the Wind load calculators.