On a Southlake standing seam roof, the paint is what you look at for the next 30 or 40 years. Two homes can have the same panel, the same gauge and the same seam, and one can look chalky and faded years before the other. The difference is usually the paint system: PVDF (often sold as Kynar 500) or SMP (silicone-modified polyester).
I’m Blake Snow. I’ve been roofing for 30 years, and we run our own roll formers for standing seam and R-panel in 24 and 26 gauge. Most articles just say “Kynar is better.” I’m going to show you what the actual warranty documents promise, because the numbers tell the story.
What PVDF and Kynar 500 really mean
- PVDF is polyvinylidene fluoride, a fluoropolymer resin that resists UV breakdown.
- Kynar 500 is Arkema’s brand of PVDF resin. Arkema’s guide spec says only a coating with 70% Kynar 500 resin can be called a Kynar 500 coating, and those 70% coatings meet AAMA 2605, which requires 10 years of Florida weathering.
- 50% PVDF coatings exist too. Arkema’s spec says they meet AAMA 2604, with a 5-year Florida weathering requirement. Ask which one you’re getting.
- Paint makers sell PVDF under their own names. Fluropon (Sherwin-Williams) is one of the common ones.
The warranties side by side
These come from published warranty documents for PVDF and SMP on Galvalume panels. A “Hunter Delta E” unit is a measured color change; lower is less fade. On the ASTM D4214 chalk scale, 10 is no chalk, so a higher number is a tighter promise.
| PVDF (Fluropon Kynar 500), McElroy Metal | SMP, McElroy Metal | SMP (WeatherXL), Sherwin-Williams | |
|---|---|---|---|
| Film (cracking, peeling) | 40 years | 30 years | 40 years |
| Fade limit, roof panels | 5 Delta E for 30 years | 7 Delta E for 30 years | 7 Delta E for 30 years |
| Dark-color exception | None stated | Charcoal and matte black: 11 Delta E on roofs | None in the section we read |
| Chalk limit, roof panels | Rating 8 for 30 years | Rating 6 for 30 years | Rating 6 for 30 years |
| Wall (vertical) panels | No separate roof/wall limits | 5 Delta E, chalk 8 | 5 Delta E, chalk 8 |
What the numbers mean on a Southlake roof
1. SMP’s promise is weaker on roofs than walls. Notice that SMP gets the PVDF-level numbers (5 Delta E, chalk 8) only on vertical wall panels. On a roof, where Texas sun hits hardest, SMP drops to 7 Delta E and chalk 6. PVDF keeps the tighter numbers on the roof.
2. Dark colors are where it matters most. Charcoal, dark bronze and matte black are popular on Southlake modern farmhouse and transitional homes. McElroy’s SMP warranty allows up to 11 Delta E fade on charcoal and matte black roofs, more than twice the PVDF limit. If you want a dark roof, that’s a strong reason to go PVDF.
3. South and west slopes fade first. Both warranties say color change may not be uniform on surfaces that don’t get the same sun. That’s normal, but a better paint keeps the difference between slopes smaller.
4. Warranty dates and paperwork matter. The McElroy warranties run from the date of shipment; the Sherwin-Williams WeatherXL warranty runs from application (film) and installation (fade and chalk). Sherwin-Williams also requires written notice within 30 days of a defect showing up. Keep your paperwork with your house file.
5. Paint warranties aren’t hail coverage. Fade, chalk and peeling are covered; dents and impact damage aren’t. That’s an insurance claim. In Texas you generally have 1 year from the date of loss to file a claim, but check your policy.
When I’d pick each one
- PVDF: high-end standing seam on a home you plan to keep, dark colors, big visible slopes, HOA neighborhoods where a faded roof stands out.
- SMP: shops, barns, ag buildings and budget projects, lighter colors, or anywhere the look over 30 years isn’t the top priority.
For gauge and seam choices, see 24 vs. 26 vs. 29 gauge and snap-lock vs. mechanically seamed. For panel makers, see our comparison of PAC-CLAD, Englert, Drexel and McElroy standing seam.
What goes on our metal roof quotes
- Paint system by name: PVDF (70% or 50%) or SMP, and the coil coater or paint brand
- Color, and whether the paint warranty has a dark-color exception
- Substrate (Galvalume or galvanized) and gauge (24 or 26)
- Panel profile, seam type and clip system
- Copies of the paint and substrate warranties, with how they start and how to file
- Free digital photo report, and our workmanship warranty from 10 years up to lifetime, depending on the job
Metal lead time is typically 1 to 2 weeks.
Talk to us about standing seam in Southlake
We install standing seam, R-panel, PBR and corrugated metal in Southlake, Westlake, Colleyville, Keller, Grapevine and across DFW. We’re certified with GAF, CertainTeed, Owens Corning, Atlas, Johns Manville, Carlisle, Tropical Roofing Products, Mule-Hide and Enviroshake, and many other roof manufacturers. We’re BBB A+ rated, with 5.0 stars on Google at all three offices: Bridgeport, Decatur and Rhome. Request a free inspection or call (817) 733-9228.
Sources
- Arkema: Kynar 500 FSF liquid coil and extrusion coatings guide specification
- Arkema: Kynar 500 product specifications
- McElroy Metal: Fluropon Kynar 500 PVDF warranty with Galvalume
- McElroy Metal: SMP finish warranty with Galvalume
- Sherwin-Williams WeatherXL siliconized polyester 40-year limited warranty
