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
Interior chimneys are at least 4" larger in all four directions than the flue they contain. A chimney containing a 12"x12" clay flue liner must be at least 20" by 20". Combustible materials must be ke ... read more