What is Roof Flashing?
The roof of a residential home serves one major purpose, and that is to be a barrier against the weather outside. The most difficult weather element to control is water, and roof flashing acts as the last line of defense against water leakage. Roof flashing is simply a piece of sheet metal — usually aluminum or galvanized steel — which is placed over joints in roof and wall construction to prevent water seeping into the house and causing damage. The major cause of residential roof leaks is a fault in the roof flashing. Roof flashing represents a very simple and intuitive engineering technique that has been known for hundreds of years. The whole idea depends almost entirely on gravity. If the flashing has been installed correctly, gravity will work with the flashing material to shed the water onto the regular roofing materials, where it is then directed harmlessly to the ground. Roof flashing is commonly used around chimneys, fan vents, plumbing vent stacks, and other items that proje
A4. Not all roofs are the same, however the flashing used is very similar. Often there are “Stains” at corner eaves present on many homes. Typically this is due to slow drainage from the roof and the water “Leeches” underneath. The wood acts like a sponge causing the stain. This is not unusual, but very common and certainly not a concern. Flashing material between 2 adjoining roofs will let the water flow off the roof and away from edges. The majority of ceiling stains come from intrusions at flashed points and protrusions through the roof, ie: vents and chimneys. Proper flashing is designed to remove moisture from the roof as so not to affect the structure.
