Flashing is the metal that keeps the intersection between the chimney and the roof watertight. This usually includes two layers. The base flashing which is woven into the shingles, and the counter flashing which is usually, in this area, lead. We can evaluate the condition of your flashing system and recommend the best option for your needs.
The photo to the left is an old stone chimney flashing repair with a new stainless steel cap. This chimney had at least six inches of roofing tar all around the base. This repair will waterproof and preserve the chimney for many, many years.