The Rise of Symmetrical Standing Seam Metal Roofs: A Game-Changing Innovation

The metal roofing industry has undergone remarkable changes over the past decade, with a standout development being the growing popularity of symmetrical standing seam panels.

What is a Symmetrical Standing Seam Panel?

If you aren’t familiar with the term symmetrical standing seam, look at the image below. Symmetrical panels have the same shape on the left and right vertical legs. In contrast, non-symmetrical panels involve different configurations on the left and right sides.

Besides a slight variation in the shape, you may be wondering what the big deal is. Symmetrical panels have quickly gained favor with installation crews because they’re much more user-friendly. Symmetrical panels allow contractors to stop and start at multiple points on the roof. In contrast, non-symmetrical panels, often called “handed” panels, require crews to start at one side of the roof and progress across in an orderly fashion-typically left to right.

Imagine for a moment that the HVAC contractor for your new building is running behind on a rooftop unit. The rest of the roof is ready for installation. With a non-symmetrical style panel, you’re at a standstill until your HVAC unit can be set, which likely means trades can’t begin any work within the building.

But if you were working with a symmetrical panel, crews could install panels right up to where the HVAC would go, literally jump over the space, and continue to install the rest of your roof. The other trades could then likely start in the building, and your contractor could simply come back and complete the section around the HVAC unit when it’s available.

Beyond installation flexibility, which is a really big deal, according to Charlie Smith, National Recover Manager for McElroy Metal, these innovative systems offer three main advantages: enhanced water resistance, superior wind uplift performance, and improved repairability.

Enhanced Water Resistance

One of the key benefits of symmetrical standing seam panels is their exceptional protection against water infiltration. "They're more watertight because of the way that the sealant is put into the cap and the way the cap sits on top of the panel seam," Smith explains.

Another significant innovation lies in the positioning of the clips. "There's no interruption of the sealant where the clips are located when you’re working with symmetrical style panels because the clip is buried inside the panel seam below the sealant in the cap," Smith notes.

This design contrasts sharply with traditional double lock standing seams using non-symmetrical panel styles, where the sealant passes over the clips, creating potential weak points.

"With a double lock standing seam, wherever there's a clip located, there's a break in the sealant," Smith points out. "If you get water over the seam, or if you get a pressure differential inside the building versus outside, you'll have water pull through the standing seam in those double lock panels where the sealant is interrupted."

Superior Wind Uplift Performance

Symmetrical standing seam panels also boast enhanced wind uplift resistance, especially when combined with multi-span clips. "We have tripled the wind uplift capacity of these roof systems by using multi-span clips which run along the entire vertical leg of the panel from eave to hip or ridge,” Smith explains.

While multi-span clips represent an additional cost, Smith notes that they are "a lot less than adding framing on the inside of the building or to the outside of the building." This makes them a cost-effective solution for achieving superior wind resistance without extensive structural modifications.

Enhanced Repairability and Longevity

Another significant advancement presented by symmetrical panels is their ease of repair. "This idea of being able to replace a panel anywhere in the field of the roof is a huge deal," says Smith. This feature is particularly valuable given the extended lifespan of modern metal roofs.

Smith highlights that U.S. Steel has increased their warranty on Galvalume^® products "from 25 to 50 years with paint, 45 without paint," suggesting that these roofs could last 60 years or more. "Given their long life expectancy, it’s nice when you can work with a system that allows you to make simple repairs to it because things happen," he adds.

This ease of repair is crucial for commercial buildings where modifications are common. "Owners are going to add penetrations, and the symmetrical panel allows you to pull the roof apart, add the penetration flashing, and then put the roof back together properly around the penetration. That's an enormous deal," Smith emphasizes.

These advantages have made symmetrical standing seam panels an increasingly popular choice in the metal roofing industry, marking a significant advancement in roofing technology and performance. As building owners and contractors seek reliable and efficient roofing solutions, the rise of symmetrical standing seam panels represents a game-changing innovation.