Above & Beyond Roofing

This is a good example of the custom metalwork you can receive for your chimney flashing, which gives a real designer look to your home.

In these four pictures the old materials are removed and new valleys, step flashing and ice and water shield are added before the new shingles go over the top, to provide maximum protection in trouble spots.

Wall flashing should be changed at all times. 
When metal is bent it creates a seam, once the seam cracks, its going to leak.
The problem with the crack is you cant see it until it is too late.
When removing the old shingles and step flashing from the wall, you are going to have some problems not opening and closing the bend on the metal of the wall flashing. If your wall has 20 step flashings on it, the wall flashing metal must open and close the least 40 times to remove all the nails.  Its old metal and the seams will crack.