The BEST way would be infrared image testing. Only top-tier roofing companies will have them, so may be hard to locate in rural areas. However, the technology is getting older, and the cameras that we ... read more
Another option, which I have not used myself, is used a lot in Houston. https://www.plylox.com/ This company sells a clip that is attached to 1/2"plywood, and you can typically get them at your loca ... read more