A properly maintained crown helps prevent moisture from penetrating the masonry and causing costly deterioration. Using a chimney crown sealer can be an effective DIY solution for small hairline cracks when the surface remains structurally sound. However, wider cracks, missing concrete, spalling, or separation from the surrounding brickwork require more than a protective coating. This... https://redbrickmasonry.ca/chimney-crown-sealer-diy-guide/