Roof flashing is a flat material used to prevent water from entering through the ceiling or other entryways. It is usually installed underneath the shingles of your roof to mitigate and redirect water. Roof flashings are made of metals, such as copper, aluminum, stainless steel, or galvanised steel.
Common Forms of Flashing
Continuous flashing or apron flashing is a long and single piece of metal. This form of flashing is often used to flex with the walls of the home itself. Joints and reinforcements may be required to keep the flashing from bursting or warping.
Certain roofing features such as chimneys or skylights may require what is known as Base Flashing. This involves using two pieces of metal to ensure water is always guided away from the roof. Unlike other types of flashing, base flashing is easy to install.
Counter flashing either goes on top of base flashing or opposite it. It is the second piece required to complete the base flashing.
Step flashing, shaped like a rectangle, is bent 90 degrees from the middle to guide water away from the walls.
There are many other types of flashing. Some are simply specific to certain additions to the roofing such as skylights, ventilation, and chimneys. For instance, most skylight flashings come with the skylight itself or are made specifically for such a situation.