Masonry chimneys are capped with a mortar ‘crown’ to prevent water from getting behind the bricks and alongside the flue, and into the house. Over time, normal expansion and contraction cycles can cause cracks to form.

Chimney crowns are another area of the chimney system that often requires repairs. This cement slab tops off many masonry chimneys and is also subject to the elements that create cracking and deterioration. If the crown is not keeping water out, it will seep down into the bricks causing further damage. Many times simple crown sealing can remedy a problem. A complete crown rebuilding is called for when the chimney crown has lost too much of its structural integrity. If a deteriorating crown is left unchecked, the repairs will be much more costly.