A roof flashing is a material that roofers install to add protection to the parts of a roof that are more prone to leaks. Flashings are available in plastic and other composite materials, but the most common material is metal. Metal flashings are coated or formulated to prevent corrosion. Galvanized steel is the preferred metal because of its durability and low cost, but aluminum, copper, and other metals are also used.
Why Are Flashings Necessary?
While the majority of a roof is made up of the main roofing material such as asphalt shingles, that material cannot cover everything on a roof. Forcing asphalt shingles to cover everything typically results in leaks, as leak-prone areas need more protection.
Leak-prone areas include those parts of the roof where there are intersections. For example, two slopes meet in a valley, so roofers install flashing on a valley for added protection against water penetration, as water runoffs are usually heavier in such intersections. Roof valley flashings bear the brunt of the water runoff and lead it to the gutters or downspouts.
Other areas where flashings are necessary are chimneys, skylights, dormers, vents, and other roof features. Such roof penetrations can easily lead to leaks if flashings are absent, compromised, or installed improperly.
What Happens When Flashings Fail?
One of the most common reasons behind roof leaks is flashing failure. Many things can happen when flashings fail and your roof starts leaking, none of them good.
A leak into the attic is a primary cause of moisture buildup. Moisture is always bad news for your roofing system. Once the moisture in your attic is absorbed by the wood structure, it can cause your roof to weaken. Ignoring this for too long leads to rot, which can damage the structure beyond repair.
If a leak affects drywall, as in the ceiling or the walls of your home, it can become waterlogged, as drywall is like a sponge when it is exposed to water. This is how mold, mildew, and fungi begin to thrive. When spores are released, they join the air you breathe indoors, causing allergies and respiratory problems.
You can’t simply scrub mold and mildew away, especially if you find them too late. It takes chemicals to poison and kill them completely so they won’t grow back, at least not for a long time. You may need a professional to do this for you. Drywall affected by mold should be removed and replaced. And if your attic has too much moisture, your roofing contractor or mold specialist may have to seal it off and use a dehumidifier to remove the moisture and treat the area. In worse cases, at least a portion of your home will be uninhabitable for days or weeks.
A failed flashing that leads to a leak can also damage your floors. You might have to spend a bit of time trying to remove stains, but if your floors are wood, you have a bigger problem. Watersoaked and swelling wood have to be dried, so this means removing the floor panels. However, they might also be deformed, so it’s highly likely that you have to replace them.
Carpeted floors are prone to mold growth, as carpets and rugs hold moisture for a long time. And if your floors are damaged by a leak, it’s also possible that your crawlspaces and even your basement have moisture.
How Do Flashings Fail?
It’s important to use durable metal flashing whenever possible. Roofing professionals typically install the toughest flashings in areas that are difficult to reach and are therefore also difficult to install flashings in. Plastic flashings may cost less than metal ones, but that cost is negligible when you realize how metal flashings can outlast others by a considerable length of time.
However, like all materials, flashings don’t last forever. Several factors contribute to flashing damage, and it’s important to know and understand them so if your roof starts leaking, you know where to look. Understanding how flashings fail can also protect you from dishonest roofers who would like to add repairs you don’t need so they can make more money off you.
The leading cause of flashing damage is temperature. More specifically, flashings sustain damage over time because of the constant changes in temperature. If you live in an area that experiences intense freeze-thaw cycles, your roof flashings are more likely to suffer damage more frequently than flashings installed in areas with moderate temperatures all year. Temperature swings can force flashings to lose their durability, causing them to come loose and become useless.
Impact can also damage roof flashings. Whether it’s the force of hail or the weight of another projectile, such as a baseball, impact can break or force flashings to come loose.
Settling can also affect flashings. You might not realize that your home is moving subtly due to soil settling. If your roof moves due to this, it can loosen flashings.
The material also has something to do with flashing integrity. Metal flashings can resist impact more effectively than plastic ones. However, if the metal is not corrosion-resistant, it can develop rust over time, causing it to weaken.
What Should You Do When Flashings Break?
The best thing to do when a flashing breaks is to call a roofer and have them replace it. It’s important to do this as soon as you notice the broken flashing, as this can lead to leaks if it rains. Even if it doesn’t rain, wherever moisture can penetrate your roof, it will, and morning dew might be enough to affect your roofing system over time.
It’s also important to determine what type of flashing will work better and last longer where an old piece of flashing has been damaged. For example, instead of regular flashing, use kick-out flashing around your chimney. Step flashing and counterflashing are also great for chimneys and other roof penetrations.
It is worth mentioning that replacing roof flashing yourself is not an ideal solution. Flashing integrity and installation are crucial when it comes to how flashing performs and how long it lasts. It’s advisable to call a pro for this job.
Get in touch with Lask Exterior Solutions, LLC, your local roofing contractor. Call us today at (815) 964-2220 or leave us a message. We offer our exterior solutions to homeowners in Rockford, IL.