copper roof flashing for asphalt shingle roofs

Roof Flashing: All About This Important Roof Component

Metal flashings are an important component of a roof. While roof flashings may not cover large areas of your roof, this component performs the task of helping to keep your roof leak-free around the perimeter.

Read on to learn more about roof flashing and how to keep yours in good condition.

Roof Flashings Function

Roof flashing is designed to prevent roof leaks. While roof leaks can occur virtually anywhere on your roof, an estimated 90 percent of all roof leaks occur at or around faulty flashing.

While there are many types of roof flashing, most consist of formed metal that are attached to the areas and joints of your roof where roof leaks are most likely to occur. Flashing covers and seals these areas to keep rainwater from seeping underneath your roof surface and onto your roof decking or even directly into your home.

Just a few of the roof areas where flashing is typically installed include around roof features, such as chimneys and skylights; at valleys; and where your roof meets an exterior wall.

Roof flashing is also installed around the perimeter of your roof to direct water away from your roof and into your home gutter system.

Roof Flashing Materials

Roof flashings can be composed of several types of metal. Each flashing type has its unique advantages and disadvantages.


Aluminum is the most popular metal used to create roof flashings. Aluminum is resistant to rust and corrosion, and can be painted in a color that complements your home. If maintained, aluminum flashing can stay in great shape for over 20 years. In addition, aluminum flashing is very affordable.

However, since aluminum is a lightweight, malleable metal, aluminum flashing can be bent or damaged by heavy impacts.

Galvanized Steel

Galvanized steel is another popular option. The steel is coated with a layer of zinc that protects the steel underneath it from rust and corrosion. Steel is heavier than aluminum, which makes it more resistant to damage from heavy impacts as well. This flashing can last for up to 40 years.

However, due to its heavy weight and strength, galvanized steel is more difficult to contour when creating and installing flashing, making installation more time- and labor-intensive. In addition, if the exterior layer of zinc on galvanized steel is damaged, the steel underneath can rust.


Copper flashing is durable, corrosion-resistant and attractive. Copper can maintain its integrity for over 100 years with proper maintenance. However, this metal is lightweight and malleable like aluminum, so it can develop dents relatively easily. Plus, this material is relatively expensive.

Roof Flashing Issues

When roof flashing becomes damaged or develops other problems, your roof is more likely to develop a leak in that area. The most common roof flashing problems are corrosion that occurs over time, flashings that become loose after severe weather events, and flashing failure due to improper installation.

While all flashing problems create potential for roof leaks, flashing damage around skylights and chimneys should be repaired immediately because when these flashings fail, water can gain direct entry into your home.

To prevent roof flashing problems, have your flashing inspected once a year and any time you suspect damage after a severe weather event. Your roofing professional can repair or replace damaged flashings.

Metal flashings are an essential component of your roof system. Contact the roofing professionals at SUNVEK to schedule roof flashing inspection and repair today. We look forward to helping you with all your questions, concerns, and issues with flashing and all other roof components. Please let us know what roofing issue we can help you with today.

More From Our Blog

Phoenix rooftop. Foam roofing is a great way to protect your roof.

Installing Foam Roofing on Apartment Buildings

Managing an apartment building is a fun challenge in many ways, but dealing with emergencies can hold you back from…

Read More
Close up of roof eaves. What do you need to know as a homeowner about this section of your roof?

What Every Homeowner Should Know About Their Roof Eaves

Your pitched residential roof consists of more than just the metal, tile, or shingles covering the surface or the underlayment…

Read More
Roof leak in a commercial building, with white walls and mold growth.

How a Leaking Roof Damages Your Commercial Building

Any indications of a leaking roof spell trouble.  But when you notice them in your commercial building, it’s particularly alarming. …

Read More