Picking the right color for your metal roof is exciting, but more considerations should be made during the decision making process besides what the color looks like. Choosing the right paint system for your metal roof is a big contributing factor into how your roof will look long term.
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At Western States Metal Roofing, we have worked with thousands of customers over our 25 years in business and have learned that color and appearance is one of the most important factors that homeowners care about when buying a roof. We're proud to offer metal roofing and siding panels in over 100 unique colors and finishes including many in the PVDF paint system.
While PVDF coatings maintain their color longer, it's also not the right fit for every roof. In this article, we help you decide if they are right for you by discussing the pros and cons of PVDF paint systems.
What Is PVDF Coating?
PVDF refers to the resin polyvinylidene fluoride. PVDF coatings use the highest quality pigmentations and consist of one of the strongest bonds known, called the carbon-fluorine bond, which adds to its durability.
What Are The Alternatives To PVDF?
- Polyester
- SMP (Silicone-modified polyester)
Polyester Paint System
A polyester paint system consists of unsaturated synthetic poly resins that are blended with organic pigments. While this paint system is the least durable, it is also the most affordable. It's rarely used for metal roofing or siding panels.
SMP Paint System
SMP paint system consists of polyester and silicone intermediates. SMP is the middle ground between the polyester and PVDF paint systems, however there is a large variation in quality within the SMP paint category depending on the specific makeup of the resin. The higher the silicone content, the better the performance of the paint as the silicone improves the paint's gloss retention and weather resistance.
SMP paint systems are primarily used on light gauge metal panels in a 26 or 29 gauge thickness. In addition, they are used more often as a metal siding versus a metal roofing because you will have less UV exposure. The main disadvantage of SMP paint systems is that the color will fade quicker when compared to a PVDF coatings system. The colors that work best with SMP paint systems are earth tones and whites as the fading will be less noticeable.
Why Is PVDF Better Than Other Paint Systems?
PVDF high performance and superior resistance to premature chalking and fading, as well as excellent chemical resistance, makes it the highly preferred paint system. When it comes to metal roofing, where the painted surface is highly exposed to damaging elements such as UV rays and debris, excellent abrasion and fading resistance is critical.
By having a superior paint system such as PVDF, the metal roof panels are able to maintain their aesthetic quality for longer than other metal roof paint systems such as SMP.
The Pros Of PVDF
- Greater resistance to fading
- Greater resistance to chalking
- Superior longevity than other paint systems
- End User Expectations
- Large variety of color options
PVDF Has Greater Resistance To Fading
The chemical makeup of PVDF gives it the ability to retain its original hue and brightness for longer than other paint systems used in roofing.
Fading, or the visible loss of original color, is something that all metal roofs face at some point. 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. By using PVDF paint, you have the greatest defense against harmful UV rays that will fade the roof's color.
Not only does PVDF paint coatings keep your roof looking more vibrant, it also helps keep your roof looking even for longer. Oftentimes, roofs that do not have adequate fade resistance will not fade evenly if one side of the roof receives more shade than the other. The side that is more often in the sun will look more dull than the side that is covered and receives less UV exposure.
PVDF Has Greater Resistance To Chalking
Chalking, or the appearance of a powdery substance that forms on the surface of a painted panel, results from the chemical breakdown of the paint's resins and pigments after being exposed to the sun for an extended period of time. While chalking on painted metal panels is inevitable, the strong chemical components of PVDF make is more resistant and delays chalking compared to weaker paint systems.
PVDF Has Superior Longevity Compared To Other Paint Systems
Other paint systems cannot compare to the lifespan of PVDF. This is even reflected when you compare paint warranties of the different systems. While the covered time period is different for each manufacturer's warranty, PVDF is usually always covered for fading and chalking for more years than SMP paint systems.
End User Expectations
Purchasing a metal roof is an expensive investment in your home. If you're going to spend that kind of money, then you want a product that will last a long time. You will want a product that still looks beautiful many years after the installation.
A metal roof can last 50 plus years, but it's a system and all of the components within it should be designed for the same period of time. You want to use a nice synthetic underlayment that has a 50 year warranty and a PVDF paint system that has the longest warranty for chalking and fading. Cutting corners on any of these components will lessen the overall longevity of the metal roof
PVDF Has A Larger Variety Of Colors
If you use a SMP paint system, you are limiting your metal roof color options to only the basic and standard colors. However, PVDF panels are available in a much wider variety of custom colors, finishes, and paint prints.
If you are looking for a unique color and design that will stand out, you will likely end up choosing a PVDF color.
Examples of unique PVDF colors include:
- Matte finishes
- Rusted colors
- Wood colors
- Zinc colors
- Copper colors
The Cons Of PVDF
- PVDF is more expensive
- Less abrasion resistance
PVDF Is More Expensive
PVDF will cost between 15-35% more than the lesser quality SMP. The greater cost is the result of PVDF being made from metal panels that are a heavier gauge and higher quality paint resins.
PVDF Has Less Abrasion Resistance
PVDF paint is soft which makes it easier to scratch compared to a harder paint such as SMP. This means extra care should be paid during transporting and installing to ensure the panel's surface does not get scratched.
Choosing PVDF Panels For Your Metal Roof
PVDF panels are popular for maintaining their vibrant appearance longer without fading. However, they are significantly more expensive and may not be the right fit for every project.
PVDF Paint Panels Typically Fit Those Who:
- Are using the panels on their home or have aesthetics as a main concern.
- Want the panel with the best longevity possible.
- Choose panels in bright and vibrant colors such as red or green.
At Western States Metal Roofing, we offer both SMP and PVDF painted panels. We have an extensive color selection between both paint systems.
The next step is to determine the color of your metal roof. This article will help you with that decision: Metal Roofing Colors: 5 Tips To Pick The Best Metal Roofing Color
If you've decided to install a metal roof, there are some additional choices that you'll have to make before the installation, including the profile, size, color, and even the paint system type.
Two of the most common paint coating systems in the architectural standing seam roofing industry are polyvinylidene fluoride (PVDF) and silicone modified polyester (SMP).
So, should you choose PVDF or SMP for your metal roof? Well, it depends.
At Sheffield Metals, we've been supplying metal sheet and coil products coated in both PVDF and SMP paint systems for over 25 years. We know that there are distinct differences between both of these coatings, which is why it's critical to know all of the characteristics before you buy.
In this article, we'll cover:
- PVDF ' what it is, the advantages, and the disadvantages
- SMP ' what it is, the advantages, and the disadvantages
- Scenarios that can help you choose the right coating
Polyvinylidene Fluoride (PVDF) Paint System Pros & Cons
PVDF is a resin made up of about 70% polyvinylidene thermoplastic fluoropolymer and 30% acrylic. Commonly referred to as Kynar 500® or Hylar ®, PVDF resins are the best protective coatings to withstand extreme temperatures, sun exposure, oxygen, humidity, and pollution particles in the atmosphere.
PVDF-coated metal is the most commonly specified and installed material in the architectural standing seam metal roofing industry.
Advantages & Pros of PVDF Paint Systems
Superior color retention
One of the main benefits of PVDF paint systems is that they hold on to their color longer than most other coil coating options. Many home and property owners specifically choose to install a metal roofing system because they know it will last decades without too many signs of degradation ' including the appearance.
Carbon-fluorine bonds, like those present in a PVDF resin, are some of the strongest bonds, which makes them 'virtually immune to degradation from sunlight, moisture, acids, pollutants, and chemicals.' (Glass Canada) These PVDF resins, in turn, protect the pigments that form the color in the paint system, which is why PVDF metal roofs and walls hold on to their color longer than SMPs and most other paint options.
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Chalking & fading resistance & better warranty coverage
Every painted metal roofing system will experience chalking and fading in some capacity over time. However, PVDF systems are specifically formulated to resist these occurrences for longer, especially when compared to SMP.
For reference:
- Fading on painted metal roofing or walls occurs when substances like water, pollution, and chemicals in the atmosphere react with the paint's pigment and diminish the color vibrance.
- Chalking is the whitish residue that can become visible on a painted or coated metal surface over time. As a panel is exposed to sunlight and UV rays, the resin breaks down and degrades. Once the resin starts to break down and the exposure continues, it loses its adhesion to the surface, and those degraded particles begin to turn white. These white chalking particles will become more apparent over time.
On top of the better resistance to chalking and fading, the warranty coverage for PVDF systems is better than most SMP systems. To illustrate how PVDF and SMP paint warranties differ at Sheffield Metals, we've put together a basic chart for comparison.
PVDF vs. SMP Warranty Comparison Chart
Film adhesion lengthFading coverage lengthFading units (the lower the Hunter unit, the better the performance)Chalking coverage lengthChalking number (the higher the chalking number, the better the performance) PVDF40 years30 years5 Hunter delta-E units for roofs & walls30 years8 rating on rating on roofs & walls
SMP40 years30 years7 Hunter delta-E units for roofs (horizontal)
5 Hunter delta-E units for walls (vertical) 30 years6 rating on roof panels (horizontal)
8 rating on rating on walls (vertical)
As you can see on the chart, PVDF and SMP have the same coverage lengths; however, the levels of chalking and fading are better for PVDF. Essentially, you can expect less chalking and fading in the 30-year fading coverage window with PVDF.
High film adhesion integrity
Along with better resistance to chalking and fading, PVDF also has excellent film adhesion integrity. As you can see on the chart above, Sheffield Metals offers a warranty covering cracking, flaking, or peeling (film adhesion) to an extent apparent on ordinary outdoor visual observation for up to 40 years.
Better for bright, vivid colors
As we discussed, PVDF is the best paint system option if you're looking to install a metal roof or wall in a bright or vivid color, such as Regal Red (which only has chalk and fade coverage for 10 years), Regal Blue, or Terra Cotta. These vivid pigments in PVDF systems will be protected and therefore stay brighter for longer than an SMP system.
Even if you're not choosing a bright or vivid color for your project and are going with a muted, Earthy, or light shade, the color will hold up great with a PVDF resin protecting it.
Cool metal roofing is defined as painted or coated metal products that reflect the sun's energy to dissipate heat. Many PVDF paint systems used in metal roofing contain innovative solar reflective pigments that make a metal roof system 'cool' and therefore help to reduce the heat transferred into a building. According to the Green Building Alliance, this heat transfer reduction can result in total cooling cost energy savings ranging from 7% to 15%. Learn more about cool metal roofing, Solar Reflectance Index (SRI), emissivity, and more in our in-depth cool metal roofing article here.
Disadvantages & Cons of PVDF Paint Systems
Experiencing demand challenges in
In early , the entire metal roofing market is experiencing a disruption in getting PVDF-coated products due to shifted demands and new expanded uses of PVDF in other industries.
We have an entire article dedicated to this topic, but to recap: PVDF is a product used to produce batteries for electric vehicles (EVs) and battery solutions for renewable energy systems, both of which are in high demand. Battery and EV manufacturers are willing and able to pay higher prices for PVDF than the traditional architectural metal construction industry. This puts PVDF manufacturers in a spot where they're more inclined to sell to the market that will pay a premium for their products, which is why more PVDF is allocated to the battery and EV manufacturers. Additionally, China is keeping much of its PVDF to assist with battery manufacturing.
In mid-January, nearly all metal roofing suppliers (including Sheffield Metals) that purchase PVDF coatings are now on allocation from their paint suppliers. Essentially, this means that we're going to be able to continue to get PVDF coatings at the level we're currently purchasing it, and maybe a little more than we have historically. However, paint suppliers (such as Sherwin-Williams) will not have enough PVDF to take on too many new customers while PVDF supplies are low.
More expensive coating option
One of the most notable disadvantages of PVDF is that it's already a higher-priced product. On top of that, PVDF is also experiencing significant price increases due to the demand issues described above.
As of early , PVDF costs about 60 to 80% more than SMP and is about 50 to 60% higher in price than 15-16 months ago. Remember, PVDF prices are expected to continue rising, creating a wider pricing gap between SMP and PVDF.
Softer paint system than SMP
Another drawback of PVDF is it's a softer, more flexible coating system. Flexibility is helpful when it comes to bendability and the forming of panels; however, the softer nature of the coating makes it more susceptible to scratching and scuffing. Contractors and manufacturers have to take extra precautions during the manufacturing, transporting, and installation of PVDF-coated panels, which is often why PVDF material has a PVC film on top of it to preserve the coating until installation.
Luckily, most small scratches can be remedied with PVDF paint pens, which are typically available from your coil supplier.
Silicone Modified Polyester (SMP) Paint System Pros & Cons
SMP, also referred to as silicone-protected or siliconized polyester, is an architectural paint system used to coat metal sheet and coil products. According to Metal Coaters, SMP paint systems blend polyester for weather resistance and silicon for gloss retention into one formula.
For reference, SMP is usually considered a step below PVDF in terms of performance in standing seam metal roofing.
Advantages & Pros of SMP Paint Systems
Superior scratch resistance
One of the most significant benefits of SMP is that it's a harder paint system than PVDF, which makes SMP-coated material more difficult to scratch. Panels with an SMP paint system can withstand a higher level of improper handling during the manufacturing or installation of a roof. You might even notice that SMP-coated metal often doesn't have any film on top of it because it's overall more scratch-resistant.
Film adhesion warranty
Another benefit of SMP paint systems is that the film adhesion part of the paint/finish warranty is usually similar to (or the same as) PVDF. For example, at Sheffield Metals, we offer a warranty covering cracking, flaking, or peeling to an extent apparent on ordinary outdoor visual observation for up to 40 years. This is the same film adhesion coverage available on our PVDF-coated products (see warranty comparison chart above).
Lower cost & more affordable
One of the most notable benefits of SMP is that it comes at a much lower price point than traditional PVDF-coated materials, making it a more affordable option for some standing seam projects. The lower price of SMP is why it's traditionally used in structural and agricultural metal roofing applications. Recent advancements in SMP formulas have expanded it into more architectural, residential, and commercial projects.
Keep in mind that different SMP paints cost more than others, including those formulated with ceramic pigments for higher fading resistance.
Textured finishes available
Another reason SMP is experiencing growth in the architectural metals industry is that textured finishes, such as Sherwin-Williams' WEATHERXL' CRINKLE FINISH or AkzoNobel's CERAM-A-STAR®, are formulated with SMP paint systems. Textured finishes are unique because they provide an enhanced visual depth on flat panels that you don't get from solid colors. Plus, it can help minimize the appearance of oil canning, which can occur with flat standing seam panels.
Best of all, these textured paint systems are typically applied to 26 or 24-gauge Galvalume, so it becomes more in line with architectural standing seam system requirements.
Disadvantages & Cons of SMP Paint Systems
Lower color integrity
The main disadvantage of an SMP paint system is that it will likely chalk and fade more than a PVDF system, especially if exposed to significant sunlight/UV rays.
The color pigments in SMP systems break down in less time because the chemical bonds in the silicone-modified polyester resin are not as strong as a polyvinylidene fluoride formula, leading to the color's fading. The same goes for chalking; as the SMP resin breaks down and loses adhesion to the surface, the particles will turn white, and the chalking will become more apparent.
However, it's important to remember that all painted metal will experience chalking and fading to some degree.
Less chalking & fading coverage
While the film adhesion on SMP is covered for 40 years, chalking and fading (up to a specific point) are only covered for 30 years. What you can see in the comparison chart above is that SMPs have different chalking and fading ratings for roof panels than PVDF systems, both of which are less-performing numbers. In essence, this means that SMPs are expected to chalk and fade more within 30 years than PVDF systems. We recommend reading the fine print of a finish/paint warranty to understand how coverage changes based on the paint system.
Not recommended for bright, vivid colors
Due to the higher level of fading and chalking with SMP panels, bright and vivid colors aren't usually recommended. Bright colors like reds, blues, and greens will noticeably fade differently than lighter grays or beiges. That's why many suppliers' SMP offerings have more earth tones or lighter colors that will better maintain the aesthetic of your roofing system. Brighter, more exotic colors are better suited for PVDF or FEVE type systems because their resins protect the color pigments for more extended periods.
PVDF vs. SMP: Which Is Best For Your Project?
To help you better choose the best paint system for your project, here are some scenarios that you can use as a baseline to measure which coating is suitable for your specific situation.
Colors & Finishes
- You want a bright, vivid, or vibrant color.
- You want an Earth tone, lighter color, or muted tone.
- Best paint choice: SMP or PVDF
- You want a textured finish.
- You want or require a cool metal roofing system with a high SRI value.
- Your project is in an area with significant sun exposure.
- Your project is in a mild environment.
- Best paint choice: SMP or PVDF
- You want a paint system that will maintain its color for decades without much fading.
Warranties
- You want a warranty with superior film adhesion coverage.
- Best paint choice: SMP or PVDF
- You want the best chalking and fading coverage in your warranty.
- You're not as concerned about chalking and fading coverage.
Price & Cost
- You don't want to spend a lot on your metal roof or have a limited budget.
- You are willing to spend more on a metal roofing system or have the budget for it.
Final Thoughts on PVDF vs. SMP Paint Systems
PVDF and SMP are both great coating options ' there's no question about it. However, the best or right choice relies on your specific needs and expectations for your standing seam metal roof.
To assist in the decision-making process, make sure you consider the following:
- Your project's budget
- Your project's location, environment, and weather patterns
- The color and tone you want
- The level of fading and chalking you're willing to accept
- The level of warranty coverage you expect
- Product availability in your area
- What your contractor, manufacturer, or other professional recommends
For over two decades, Sheffield Metals has been helping our customers and their customers choose the paint system that is best for their projects. Whether it's SMP, PVDF, or beyond ' we're dedicated to working with you to get the paint solution that will work best in your environment.
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