According to the Brick Industry Association, chimneys require special attention and maintenance to prevent costly damage caused by water penetration. Because chimneys project above the roof line, they are vulnerable to the elements. Nearly every chimney you encounter has signs of water damage! The first step is to determine the cause and then find the best corrective measures. ChimneySaver, the first product developed specifically for chimneys, has been used successfully by leading chimney professionals for nearly 20 years. It reduces water penetration into the masonry by 99.9%, according to ASTM tests conducted at the University of Wyoming.