Reference wind speed: A Quick Guide from Scaffcalc

The reference wind speeds specified in Boverkets konstruktionsregler (EKS) are average values over a period of ten minutes. However, during these ten minutes, there may be higher wind speeds in the form of gusts that occur for shorter durations. It is these gusts that a structure must be designed for. Within the regulatory context, two wind speeds are used to represent gusts: the three-second mean wind speed and the one-second mean wind speed.

The so-called reference wind speed is defined as the average wind speed over a duration of ten minutes at a height of 10 meters above a horizontally homogeneous surface and a return period of 50 years. To account for gusts lasting three seconds and one second respectively, form factors are used.

Use the map on your right-hand side to determine the reference wind speed for your next project. Building in Stockholm? Then the reference wind speed should be 24 m/s.