
What is Flashing?
If you have ever had your roof repaired or replaced, you probably know a little bit about roof flashing. Repair of the roof flashing is as important as replacing shingles, but yet, it is the unnoticed component. Maybe you’re thinking to yourself, “Do I really need roof flashing?”, and the answer is yes! And your next question is “Why? What is the purpose of roof flashing?”
First, we’ll tell you why it is called ‘roof flashing’. There isn’t any certain reason that has been found about the terms flash and flashing origin. It is thought to be a Middle English verb that originally was ‘flasshen’, meaning to sprinkle or splash, a lead strip. Sometimes it was referred to as ‘the apron’ when installed around a chimney.
Today, the reference of roof flashing is the strips of thing metal that is installed on a roof in areas where water can seep in around the roofing materials and roof protrusions. The metal is usually a galvanized steel but can be aluminum, copper, or stainless steel. With the understanding of where and why we have roof flashing, repairs are easy to understand their importance.
Do I really need roof flashing?
Absolutely! As we’ve mentioned, roof flashing protects several areas of the roof components, like the chimney, skylight, and other protrusions, from water seeping in , causing damage with leaks. Roof flashing keeps the water from getting under shingles and down walls.
Any area where water runs through a crevice or corner, there needs to be roof flashing. This is why it important to have roof flashing repaired as soon you notice a problem. With roof flashing loose or missing, water can get in around the chimney or down inside walls. Even the gutters that are made to direct water away from your home needs roof flashing, so the water runs into the gutters.
Is roof flashing required by code?
It will depend on where you live but in most areas, yes, roof flashing is a building code requirement. You would be hard pressed to find a professional roofing contractor that tells you roof flashing is unnecessary. Even if the local building code where you live doesn’t require roof flashing, an experienced roofing contractor will insist it be installed.
What are the different types of roof flashing?
There are two basic kinds of flashing, one being an external flashing and the second is an internal flashing. The external flashing prevents moisture from penetrating where walls intersects with the roof. The following are the different types of flashing used in most roofing jobs:
- Continuous Flashing. Also referred to as apron flashing, is a long single piece of metal that carries water from the shingle to off the house.
- Base Flashing. A roof feature like a chimney, requires two pieces of flashing to ensure rain will always meet a flashing surface to direct it off the roof
- Counter Flashing. Installed opposite of base flashing, this piece completes the team for base flashing.
- Step Flashing. A rectangular shaped flashing in a 90 degrees angle is used for wall flashing in layers with multiple other pieces of the same type of flashing. This is to assure that water is flowing away from walls.
- Skylight Flashing. This type of flashing comes with new skylight installation, but existing skylights need new flashing with new roofing.
- Valley Flashing. Open valleys are where two roof angles come together and is a critical are to protect from leaking. When there is a need for roof flashing repairs in this area, it must be addressed immediately.
- Drip Edges. This flashing is installed along the roof edge, allowing water to drip off without causing damage to your home.
- Kickout Flashing. This flashing is used to bridge the gap between the step flashing and the gutter runs to direct water away from a wall and into the gutter.
What is the best roof flashing?
When you are selecting flashing for your home, the budget will be the first concern. You should choose a flashing material that is long lasting so that you won’t need to worry with roof flashing repairs. Common choices of roof flashing are:
- Aluminum: The most popular of all materials because of the cost factor but still offers quality.
- Copper: The most expensive of all roof flashing materials. It is strong and an eye catcher.
- Membrane: If you’re looking for a drastic difference, this strong tape type of roof flashing give you that difference and still protect your home against the elements.
How do you fix roof flashing?
You can always call an experienced roofing contractor for roof flashing repairs. Or you can do you own roof flashing repairs Repair corroded areas and small holes with roofing cement. Holes that are 3/4 inch diameter, place a patch of the same type of flashing material and roofing caulk. If the flashing is against the chimney or a brick wall, use a masonry caulk for sealing the gaps and joints.
How do you add flashing to an existing roof?
Measure the area that needs flashing and purchase the like-same material as the other flashing. Using roofing cement and galvanized nails, place the flashing where needed. Step flashing along the chimney will need to be layered with the shingles.
What can I use for roof flashing?
Steel is the most common metal for roof flashing. The roof has a clean appearance, and it is a budget friendly material. If there is room in the budget, go with the aesthetic upgrade of copper flashing.

Sealing It Up – Can roof flashing be painted?
Yes, old can usually be painted with basic house paint. New roof flashing should be primed first, then use a paint for exterior surfaces. Keep in mind, once painted, it will need repainted every 3 to 5 years.