In this particular photo, the concrete used on the chimney cap has cracked. This can be repaired either with the use of Crown Seal elastomeric compound, or by removing and pouring a new cement cap.
This particular chimney the deterioration was caused by years of exhausting an oil furnace and not having a rain cap in place. This chimney will need a new stainless steel liner installed.
This chimney has improperly placed sill stones installed on the top of the chimney. Water was able to penetrate between the stones and deteriorate the masonry. The top of the chimney will need to be rebuilt and a new concrete cap poured.
This chimney was built improperly. There was no top flue tile installed and water freely sat inside the chimney. As a result, this chimney will have to be tuckpointed and a new top flue and concrete cap installed.
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