CSA A123.21
In 1994, the National Research Council of Canada (NRC) formed the Special Interest Group for Dynamic Evaluation of Roofing Systems (SIGDERS). Its objective was the development of a device that could simulate the dynamic forces created by strong winds and gusts, and their effects on mechanically attached roofing systems. In addition to taking into account the variations caused by systems’ components and materials, SIGDERS included in its mandate the elaboration of a protocol which would conform to local construction codes while taking into account known wind uplift factors.
To the present day, static simulation was the only available method to compare roofing assemblies with winduplift resistance. With dynamic simulation it is now possible to reproduce actual conditions caused by wind on roofing systems.