At A&J roofing, we replace all flashing if needed. Flashing prevents water from entering your home and preventing serous long term damage. Flashing can be found on many areas the roof. Many roof leaks haven't anything to do with roofing material. More often, they are the result of faulty or poorly installed flashing. Most modern flashing is constructed of galvanized sheet metal or aluminum,. Flashing typically can be found around a chimney where it meets the roof, and along walls were they meet the roof. There are several reasons why flashing can fail. For example, a flashing system that integrates the use of an asphalt compound or caulking material will fail after exposure to the outside weather elements after a period of time. Ultraviolet rays from the sun will deplete these products of their elasticity and will result in cracking. These materials must from time to time, be replaced. The same holds true for the counter flashing that surrounds a brick chimney and walls. The mortar joint into which the counter flashing is embedded might eventually be the source of a leak as the mortar joint gives way to freeze/thaw cycles. We seal the brick with a high quality waterproofing material that prevents this from occurring. The big mistake that most folks make is to wait for Mother Nature to determine if their flashings are leaking with the first winter's rain.  When it comes to flashing around vent pipes, pay special attention to the joint between the flashing and the vent pipe, called the "pipe boot collar." Often, the collar is coated with an asphalt material or consists of neoprene, both of which can become brittle with prolonged exposure to the sun promoting a leak.