A large percentage of my work is inspecting and repairing poorly installed chimney flashings and roof leaks.

The chimney flashing pictured below started leaking not long after it was installed. This roofing job was for a new homeowner who decided to replace the deteriorating roof shingles on their house along with installing new siding. There were leaks aroung the chimney which was attributed to the roof to chimney flashing. They were not too happy to find new water leaks into the newly remodeled interior walls below after the new roof was installed.

Here the roofers decided to go right over the existing chimney flashing. The original was copper sheet metal. Both step and counter flashing. The original counter flashing looks like it was installed properly. The flashing bent, fastened and sealed into the mortar joints of the chimney. But the mortar was deteriorating at some of the chimney stone joints and possibly beginning to leak as well. Unfortunately, the new roofers could not be bothered to repair the original flashing which would have lasted for as long as the new roofing material. Instead they cut some cheap aluminum flashing metal and tacked it right over the original. You can see the original copper flashing at the lower corner where the chimney meets the roof and valley.

The new metal was cut to the approximate size of the original flashing and nailed straight into the face of the flashing and chimney, then caulked with cheap roof sealant. There was no attempt to bend the top edge to insert into a mortar joint, or to even bend the edge slightly to hug the chimney stone. In most places the new flashing covers the original and the mortar joint, and is butted and caulked to the stone.

It is at the top of the chimney counter flashing that the new leaks begin. The caulking has dried out, and the constant expansion and contraction of the aluminum flashing has caused the seal to break. Water flowing down the chimney stone runs against and behind the new chimney flahing. Then it finds the holes in the unrepaired original flashing and leaks into the house.