Snow Load on Roofs - Monitoring Flat Roofs

Task

Although there are many building regulations and norms existing which rule the statics of flat roofs, it happens that the maximum load is reached or even exceeded in case of heavy snow load. Especially endangered are existing buildings and older flat roofs. Dangerous situations often happen in occasions with heavy snowfall followed by rain or snow-rain. The water is accumulated by the snow pack on the roof and therefore gives further weight. To assess the current load most often empirical data is missing. To clear the roof of snow can be expensive but also dangerous. Not to clear the snow of the roof can in extreme cases lead to a big disaster also with endangered people.

Solution

Through the installation of a snow scale SSR the exact weight of the snow pack is determined. The measuring data are the basis to decide whether the load on the roof is getting close to the critical maximums or if it already exceeded the maximum. Precocious decisions about needed measures can be taken. Decisions like for example clearing of the snow from the roof or closing the building for people. Especially in cases, where further snowfalls (or rain) is expected, this is a very important advantage. The SSR is used for large flat roofs as for example at industrial facilities, railway stations, supermarkets, sports or recreational facilities, schools or warehouses.

Implementation

The snow scale is simply put on flat roofs, with a maximum inclination up to 5 degrees. No structural construction at the roof itself is necessary. For very large flat roofs the installation of several snow scales at critical points on the roof is recommended. The system output is a 4 ... 20 mA signal, which is integrated in the technical building system. If needed maximum values can be fixed with the possibility to send a warning signal or to set an alarm.

Further impressions