Roof Nav Class 105 Rating

Failure can involve any number of events such as delamination of the roof seam membrane tear screw pullout etc. Wind uplift rating class 1 60 1 75 1 90 1 105 etc is determined by the least wind resistant construction usually the old roof. Existing class b or c rated roofs will require use of gypsum board to achieve a class a rating otherwise the new roofing system will retain existing ul rating.