Hello. As you point out, the leaks are most likely coming from two places: 1 - the join between the addition and the original roof structure, and 2 - the chimney area. Our rule is that chimneys over 18" in width must be cricketed (the industry consensus is between 18" - 24"). Additionally, the proper installation of a chimney flashing involves the use of a reglet which requires grinding into the chimney brick to a depth of 1" so that the flashing is actually fixed inside the brick (rather than simply being tarred and tacked to the oustide).

You mention that the addition has a low slope. The roofing material used should take this into account. It is difficult to comment without knowing the precise slope, however if you have a 1:12 - 3:12 pitch, be wary of installing shingles as snow & ice can back-up quite easily.

Please feel to contact me if you would like additional advice or information. I will try to point you in the right direction for your geographic location.

David Mackey, Vice President

MACWEST Steel Inc.

what is the pitch and what roofing material is used?

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