By: Lauren Risotto on October 26th, 2020
Do Metal Roofs Fade Over Time?
If you have any experience buying something red, whether it be a shirt, hair dye, or even a car, then you should be familiar with what happens to that same red after some time spent outside in the sun. It starts to get dull, and overtime turns into a pale version of a color that barely resembles its former beautiful, vibrant self.
This is the result of the unfortunate and unavoidable nuisance known as fading. Fading refers to the visible loss of color. Unfortunately, metal roofs are prone to fading and losing their original vibrancy over time.
At Western States Metal Roofing, we've worked with thousands of customers and have learned that color is one of the most important factors that homeowners care about when buying a roof. As a result, we've made sure that we manufacture metal panels for roofing and siding in hundreds of colors.
In this article, we’re going to discuss why fading occurs and how a paint warranty can cover your roof if your roof color fades excessively. After reading this article, you’ll be able to better determine if the color you have in mind for your roof is the best option if color fading is a big concern for you.
Why Do Metal Roof Colors Fade Over Time?
The color of a metal roof fades overtime because the chemicals in the paint’s pigments start to break down from excessive exposure to the sun. While UV rays are a major contributing factor that causes fading, other factors include moisture, salty air, chemicals in the atmosphere and pollution.
Your roof also will not fade evenly if one side of the roof receives greater exposure to the sun than the other. The side that is more often in the shade will look more vibrant than the side that is more often in the sun.
Metal Roof Colors That Don’t Fade
While fading will eventually occur with any color, there are some colors where color loss is less prominent.
So, you’re probably asking yourself then: Which color will fade less?
When choosing your roof color, there are a few considerations to keep in mind that can make color fading appear less obvious. We will go over these in the categories below.
Lighter vs. Darker Colors
Lighter colors such as tan, grays, or white have less fading than darker colors that are more vibrant. This is closely tied to whether the color’s pigment is organic or inorganic.
Organic vs. Inorganic Pigments
Colors made from organic pigments tend to fade more quickly than inorganic pigments. Inorganic colors (beiges, browns, tans, and other earth-tone colors) have pigments that are less likely to break down compared to organic pigments (reds, blues, greens).
Matte vs. Glossy Colors
Matte colors are less prone to noticeable fading than glossy colors. Matte colors have become a popular trend used in homes and commercial buildings. This is why matte roofing is now available in a wider variety of colors than ever before.
Paint System: SMP vs. PVDF
The paint system that you choose plays a role in how well the color of your metal panels holds up. This is directly tied to the quality of what each paint type is made of.
While the two main types of paint systems, SMP and PVDF, are getting closer in quality, PVDF is still seen as being superior to SMP.
Also known by its generic name, polyvinylidene fluoride, PVDF coatings use the highest quality pigmentations and consist of one of the strongest bonds known, called the carbon-fluorine bond. This chemical structure gives PVDF the ability to resist absorbing UV radiation, which is the main cause of fading.
On the other hand, SMP paint is made from polyester and silicone. While the silicone improves the gloss retention and weather resistance of the coatings, the polyester absorbs the UV radiation which breaks the paint apart. Every type of SMP has different levels of polyester and silicone in it. For the purpose of avoiding fading, more silicone and less polyester is better.
For more information about both paint systems, we recommend reading:
Best Paint For My Metal Roof Panels: SMP v. PVDF
Is Color Fading Covered Under A Metal Panel Warranty?
Color fade is covered under a metal panel paint warranty. However, the color has to be faded to a certain level to qualify for coverage under the warranty. Because every paint warranty is different, the specific amount of fade needed to qualify varies.
How To Measure Color Fading On A Metal Panel
Since everyone sees color slightly differently, color integrity of a panel is determined by computer software that reads the color revolve around tristimulus values. The end result is represented by Delta E. Delta E is a mathematical computation of paint’s 3 different color scales.
The 3 scales are:
- L = Measures lightness and darkness
- A = Measures Red and Green tones
- B = Measures Yellow and Blue tones
The Delta E takes the 3 scales of L, A, and B and turns them into one single number.
The bigger the delta, the bigger the color change. So a roof with a delta change of 7 has more fading present than a roof with a delta change of 4.
When you’re buying a metal roof you want a paint warranty with the lowest delta number for fading.
How Much Color Change Is Needed For A Warranty To Cover Fade?
Generally, you need a Delta change of 5 for a vertical wall panel and a Delta change of 7 for a non-vertical roof panel in order for your fade claim to be covered.
A delta change of 1 is hardly noticeable while a 5 or 7 has more substantial color loss. In order for your claim to be covered, the color loss of your panels has to be significant.
Every paint warranty is different so it’s important to verify the delta changes within the paint warranty.
How Should Fading Affect Your Metal Roof Color Choice
When you have your heart set on a particular color for your metal roof, fading might not be enough of a reason to change your mind. While fading is inevitable on any metal roof, even experts in the paint industry have noted that fade is ultimately not a deciding factor in the color people choose.
However, it’s important to know the risks and keep in mind, especially if the aesthetic of your roof is a top priority for you.
A roof is less likely to show fading when:
- The panels are in a PVDF paint system.
- The panels are in a lighter, inorganic color.
- The panels are in a matte finish.
- The roof does not receive excessive sun exposure.
- The roof is not located on the coast.
- The roof does not receive excessive moisture
Remember that fade is covered by most metal paint warranties. How long the fade warranty is for varies depending on the manufacturer. For everything you need to know about paint warranties and fading we recommend reading:
Analyzing Paint Warranties For Metal Roofing And Siding