The home inspection experts at AmeriSpec of Canada offer information on chimney types and their maintenance. I have noticed that there are damaged bricks on my chimney above the roof line. What has caused this and what needs to be done to correct it? A chimney is designed to exhaust products of combustion from a fuel- burning appliance to the exterior of the building. A masonry chimney is typically built on its own footing and foundation with brick or concrete block on the exterior. Flaking Flaking sometimes occurs on a masonry chimney due to the moisture in the exhaust gases that are a product of combustion. The moisture gets absorbed into the brick and freezes in the winter when the warm exhaust gases stop flowing out the chimney. When water freezes, it expands. Over time this freeze-thaw cycle leads to deterioration of the brick, clay tile, and mortar. The damage…