MR-24 Roof Clips Explained: The Small Part That Makes a Big Difference
When people talk about Butler Manufacturing’s MR-24® roof, they usually mention its legendary weathertight performance and decades-long lifespan. But there’s one small component that deserves just as much credit: the MR-24 roof clip.
These little pieces of stainless steel are the secret behind the roof’s strength, flexibility, and long-term performance. They may not look impressive, but they’re what make the MR-24 roof system one of the most durable and reliable in the world.
Let’s take a closer look at how Butler’s roof clips work, why they outperform typical standing-seam clips, and how they help buildings stay leak-free for decades.
What Does a Roof Clip Actually Do?
In any standing-seam metal roof, clips are what connect the roof panels to the structure. They hold the panels down against wind uplift while allowing them to move with temperature changes.
That movement is important. Steel expands when it’s hot and contracts when it’s cold—sometimes several inches across a large roof. If panels can’t move freely, they’ll buckle, warp, or tear at the seams. Over time, that’s how leaks start.
The MR-24 clip was engineered to prevent exactly that. It locks panels firmly to the purlins (the horizontal framing members) but lets them slide freely as the temperature changes. It’s a “floating” system—strong where it needs to be, flexible where it counts.
The Secret to Thermal Movement
Most roof clips claim to allow movement, but few do it as smoothly as the MR-24 clip. Each clip’s base is bolted to the purlin, while a stainless-steel tab connects to the roof seam. That tab is designed to slide back and forth without loosening the roof or damaging the panel.
Butler went a step further with several patented details:
Concave clip surface: The clip top is slightly curved, so it won’t gouge or cut the panel as it slides.
Triangular sliding bar: A small stainless-steel bar, coated for low friction, lets the seam glide smoothly with minimal resistance.
Stainless-steel tab: About 50% stronger than the mild steel used in typical clips, it resists bending, corrosion, and stress cracking even after decades of movement.
Together, these features give each panel up to 2.5 inches of total expansion and contraction—more than most standing-seam systems allow. That’s why MR-24 roofs hold up in extreme climates, from the frozen north to the desert southwest.
Leak Prevention: Built from the Clip Up
The clip’s flexibility doesn’t just prevent damage—it’s also key to keeping the roof watertight.
The MR-24 roof uses a 360° Pittsburgh double-lock seam, the same type of joint used in soda cans. Inside that seam is a continuous bead of factory-applied sealant. Once the panels are seamed together on site, the clip and the sealant create a solid, weathertight joint that’s nearly impossible to separate.
Because the clips let the panels move independently, that seam never twists, cracks, or pulls apart. In other roofs—especially those with snap-together seams—thermal stress often causes the joints to loosen over time. Butler’s floating clip keeps everything aligned, tight, and sealed for decades.
That’s one reason MR-24 roofs can carry top performance ratings like UL Class 90 and FM I-180, proving they can handle intense wind uplift and heavy weather without leaking.
Precision Installation: Factory-Punched Perfection
Another reason MR-24 clips perform so well is how precisely they’re installed. Every roof panel and structural purlin comes from the factory pre-punched with matching holes.
That means the clips line up perfectly—no field drilling, no guesswork, no measuring. Crews simply drop each clip into its pre-punched spot and fasten it using Butler’s high-strength Scrubolt™.
This small detail eliminates the misalignment issues that can plague other systems, where installers drill holes by hand and hope everything lines up. Pre-punched accuracy also helps the seams close perfectly when the panels are locked together.
Each Scrubolt has roughly twice the pullout strength of a standard self-drilling screw, so fewer fasteners are needed. That reduces installation time and potential leak points while increasing long-term strength.
Strength in the Details
You won’t find weak materials in a Butler clip. Each one is made from stainless steel, not painted or plated mild steel. The stainless tab resists rust even in humid or coastal environments, and the cadmium-coated sliding pin prevents galling (metal-on-metal sticking).
That attention to material quality gives the MR-24 clip exceptional wind and uplift performance. It’s one of the reasons Butler can offer 25-year non-prorated weathertightness warranties—something many competitors won’t match.
Even the sister product, the Butlerib® II roof, benefits from this design philosophy. While it’s a through-fastened system, it uses factory-slotted holes to allow slight movement and prevent stress cracking. Combined with the unique purlin-bearing leg and Lock-Rivet™ fasteners, it delivers an impressive 10-year weathertight warranty of its own.
Designed to Work with Insulation Systems
Butler’s roof clips aren’t just strong—they’re smart. They’re designed to integrate perfectly with the company’s advanced insulation systems, like TBS™ and ThermaLiner™.
TBS (Thermal Barrier System) installs insulation above the purlins, held by special brackets and thermal spacers under the clips. This design reaches high R-values—up to R-34—without crushing the insulation or breaking the vapor barrier.
ThermaLiner™ adds a steel liner panel below the roof, creating a finished interior ceiling and space for even more insulation. It can achieve effective R-values as high as R-38.7 while maintaining a clean, professional look inside.
Because the MR-24 clip system can handle movement and loads so efficiently, it works seamlessly with these insulation options. Builders can meet tough energy codes without sacrificing roof performance or risking leaks.
Compared to Typical Roof Clips
To understand how far Butler’s clip design stands out, it helps to look at what’s common in the industry.
Most standing-seam roofs use snap-together panels with basic clips made from galvanized steel. These clips usually allow minimal movement—often less than an inch—and their edges can wear against the roof panel coating. Over time, this leads to scratches, rust spots, and leaks.
They’re also installed with self-drilling screws that can misalign easily and loosen as the building moves. Once a clip loosens or corrodes, it’s difficult to repair without replacing panels.
By contrast, Butler’s clip system was engineered from the start as part of a complete roof assembly. Every clip, bolt, and seam is designed to work together. The result is a roof that stays tight, quiet, and perfectly aligned for decades, even under heavy thermal cycling and strong winds.
Why It Matters to Builders
For contractors and owners, the benefits are clear:
Faster installation thanks to factory-punched alignment.
Fewer leaks because seams stay tight and sealant stays protected.
Less maintenance—no loose fasteners or corrosion-prone parts.
Higher energy efficiency when paired with Butler’s insulation systems.
Stronger warranties backed by decades of proven performance.
Simply put, the MR-24 clip is one of those rare engineering details that solves multiple problems at once. It keeps the roof moving, sealed, and strong—all with minimal maintenance.
The Takeaway
The MR-24® roof clip may be small, but it’s part of the reason why thousands of Butler roofs around the world are still performing perfectly after 30 or 40 years. Its clever design allows movement where it’s needed and strength where it’s critical.
When paired with Butler’s precision manufacturing and integrated insulation systems, it creates a roof that’s truly built to last.