I enjoyed reading “Cricket Retrofit” (1/09) by John Carroll; we also receive calls about improper or nonexistent chimney flashings. We add some extra measures to ensure a leak-free chimney and have had great success.
At the chimney corners, we brake the copper and solder the joint to make it watertight (see photo). When installing the counterflashing, we make a continuous cut above the step flashing parallel with the roof surface. We then brake a continuous counterflashing for each side of the chimney and once again solder the joints.
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