The current New Jersey Edition of the International Building Code (2006) with amendments requires buildings, both commercial and residential, to have a ground snow load of at least 35 lbs. per square foot. This does not include any drifting snow and numerous other factors, but is the basis of design for roof structures. The Town of Dover’s Building Department uses this calculation, other municipalities may have different snow wind load requirements depending on their geographic location.
So how do you determine the weight of the snow on your roof? Weigh it! Cut out a one foot by one foot by height of snow and put it in a container. Now place the container on a scale; minus the weight of the container. If the weight is nearing the 35 pound limit, the snow needs to go. Call a licensed roofing contractor to do the work. It is not advisable for homeowners to remove snow from their roofs for safety reasons. Professional roofing contractors know how to put fall protections in place and are sensitive to electrical wires in the vicinity.
If you are experiencing damage from ice dams, which causes interior water damage to walls, ceilings and insulation, contact your insurance company.
The Building Departments role is not to inspect roofs for snow load concerns or determining existing roof load design. This is the role of a Licensed Structural Engineer. In the event of a roof collapse or structural compromise due to sag and buckling from excessive snow load please contact Dover Police and Fire at 911. The Building Department along with the Fire Department would then follow up to:
• Inspect damage to building
• Determine if the building can be safely occupied or not
• Post building and secure utilities if structure has been compromised
• Require owner to retain structural engineer to determine what corrections are needed
• Follow up to verify that structural corrections are complete and allow for re-occupancy