A complete study of the most recent data on the corrosion of metals, refractories, and various chimney linings coupled with a comparative thermal study of nine chimney systems using a 24" ID model with 40' of breeching and 100' of chimney at 70°F and zero wind velocity and 30°F and 15 miles per hour wind velocity. Flue velocities of 15, 25, 35, and 55 were considered in all cases to show the effect of flue velocities on thermal characteristics.