After a tree went through my roof almost 8 years ago, I got a new roof (2004). It just started leaking last week when a piece of the flashing that was not installed finally started leaking through the felt paper that was installed.
My chimney and roof resemble this (it is NOT my chimney; my chimney is vinyl sided, but the gable meets in the middle of the chimney like this does)
My question is how do I flash behind the siding at the peak of that gable? My chimney is missing a piece of the flashing below the peak of the gable, but I when i remove the siding to reflash the lower missing piece, I may have to replace that peak flashing as well.
What shape does that flashing need to be? I know it needs to go up the chimney 3-4" and back 2-3" under the shingles..but how do I make that shape with the flashing material (aluminum)?