Abstract: A roof sensor for a vehicle is provided. A sensor is mounted in proximity to the roof of the vehicle for monitoring the deformation of the roof caused by impact during a crash, particularly when the vehicle rolls over. A vehicle safety system is also provided. A sensor, mounted in proximity to the roof of a vehicle, monitors the deformation of the roof. A controller is connected to the sensor, a safety device, and a vehicle communication device. Based on the severity of the deformation of the roof caused by an impact, the controller activates the safety device to prevent injury to vehicle passengers and communicates the status of the vehicle to a third party such as emergency services.