Chimneys can be within a refurbishing or repair turn to. It was e.g. necessary to apply a flexible liner in the chimney from your home. After that need repair from the unlocked portion of your chimney. Again, chimney sweeps can take steps, such as bricklaying and plastering.
Chimneys out, have a lot to endure. Wind and rain do year after year their attack on the chimney. If the chimney outside on the roof performing his duties, he also looks closely at the condition of your chimney. Many chimney sweeps also have knowledge of these matters. They have in the (recent) past, mason followed a separate course chimney. They know how a chimney can be rebuilt and how repairs can be made. Many chimney sweeps bricklaying, apply lead or re-grouting.