Building age and type, insufficient drainage, ice formation and drifting and sliding snow may cause snow load-related building collapse during the winter. Therefore, commercial, school and public buildings should develop snow removal plans that include fall preparations, monitoring, and snow removal processes.

Fall Preparation
The plan should include a structural engineer’s evaluation of the building plans, roof condition, seals, flashing, drainage and ventilation. The engineer should also check for internal leaks, hanging sprinklers, and structural damage in the ceiling, framing and walls. Damage and weaknesses should be repaired based on their severity. You may want to designate a snow storage area away from the building and identify how roof dangers, such as skylights and gas lines, are marked to ensure safe snow removal.
Winter Monitoring
Snow load should be monitored throughout the winter. Measurement of roof snow load is typically calculated based on roof characteristics, amount of snow on the ground and snow type. However, factors such as rapid weather fluctuations, drifting around roof structures and roof elevation changes may also affect the load, making manual monitoring challenging. Therefore, you may want to include automatic load monitoring systems in your plans for removing snow.
Snow Removal
Snow may need to be removed from the roof based on snowfall rate, structural integrity and residual snow from previous storms. You may want to retain a roofing contractor to help remove the snow as safely as possible and reduce the likelihood of the roof being damaged during the process. General snow removal guidelines suggest starting with the center of the building and working out or using a monitoring system that identifies the areas that are experiencing the greatest loads so they can be cleared first.
If you are in an area that typically gets lots of snow, protect your roof by preparing in the fall, monitoring during the winter, and removing the snow in a timely fashion. Being prepared will help you weather the snowstorms more easily.