Toledo Roofers: Article About Chimney Flashing
Chimney flashing is an important component in waterproofing a house. Installing chimney flashing is different from installing other types of flashing since there are elements of both masonry and carpentry in the process of flashing a chimney.
No matter where on a roof a chimney is, the same principles for flashing principles are applied. One basic idea is that where two pieces of flashing are working together, the upper piece overlaps the lower. This keeps water flowing down the roof. Toledo roofers study how the water flows around the chimney before installing flashing.
Common materials used to create chimney flashing are copper, aluminum and steel. Copper has the advantages over the other two metals of not corroding, even when stuck in wet cement, and of bending easily while keeping its shape. It also changes to an attractive greenish color, called a patina, over time. However, copper is more expensive than both aluminum and steel.
The metal used in flashing must be bent. The best way to do this, if possible, is in a machine shop before installation. This way, the bends are tight and will fit better. Metal is generally cut on the job site with tin snips as needed.
There are three types of chimney flashing: base flashing, step flashing and counterflashing. Base flashing is fastened at an angle to cover the exposed joint between the chimney and the roof.
The roofers from Johnson Construction of Toledo OH would be happy to answer any questions you have about residential roofing or siding.
It keeps water moving down the shingles towards the gutters.
Step flashing is bent and cut around the corners of the chimney. It also runs up the sides of the chimney in a manner similar to steps, hence its name. The pieces are woven together in a specific way. They can be soldered together or attached with caulk.
Counterflashing is attached to the chimney itself. Its purpose is to propel water flowing down the sides of the chimney out onto the base flashing and eventually down the roof to the gutters.
Counterflashing must stay attached to the vertical wall of the chimney. Therefore, it is often embedded into the mortar of the joints when stonemasons build the chimney. The stonemasons will bend it upwards after it is attached so that the roofers can do their work and later bend it back downwards to overlap the base flashing. The counterflashing may also be attached after the chimney is built by cutting into the mortar with a diamond blade to create a groove to hang it from. Chimney flashing is more complicated than other types of roofing flashing, but when installed properly on a structure, it can outlast the roofing materials themselves.