Design & Build With Metal: Tin Or Corrugated, It’s Metal Roofing: Industry Terms, Pt. 1

I recently received a phone call from someone who had found our site when looking for information about a metal roof that he planned to put on his house. To be precise, he told me that he wanted some information on “tin” roofing. I wasn’t surprised to find that he actually meant metal roofing rather than tin, and I was soon able to offer the information that he needed.

As I ended that phone call, I thought about how important language is within the construction industry. There are specific terms used to describe all parts of a building, from the foundation to cupola, yet virtually every item has names that can be used interchangeably. One person’s roof slope is another’s pitch. You say pole barn, I say post frame.

Metal construction products have multiple names that—while understood by many—can still cause confusion to others. So, I’d like to offer a bit of help in sorting out some metal construction terms that you may encounter…while pointing out the version that you’re most likely to find as you navigate through DesignandBuildwithMetal.com. I’ll start with some metal roofing terms, arranged alphabetically, and then move on to buildings and walls in the future.

Batten Seam Roofing: This is a form of concealed-clip metal roofing. Instead of being fastened through the panels, the panels are held to the roof deck or purlins by a concealed clip. A small metal batten cap/strip, that runs eave to ridge, is used to secure the adjacent panels at their raised seam. It’s not uncommon for some people to refer to all standing seam roofs as having batten seams. A good rule of thumb is to determine if a separate cap is used to seam two panels together. If so, it’s a batten seam.

Concealed Clip or Hidden Clip Roof: The concealed clip (as noted above) is used to attach batten and standing seam roof systems to decking or purlins. Clips are designed to allow for thermal movement of the metal roof system as temperatures change—this has led to the Floating Roof description that is used frequently. Concealed Clip is the more common term, but hidden clip sneaks in occasionally.

Corrugated Roofing or Corrugated Panels: In a traditional sense, corrugated roofing has a wavy appearance when viewing the panel from its edges. Picture a line of S’s lying on their sides and you’ll get the idea. The word “corrugated”, however, is often used to describe a much wider variety of Ribbed Panels.

Exotic Metals: This term once described a variety of metals that includes just about anything other than steel or aluminum…such as copper, zinc, stainless steel, etc. Currently, a movement is underway to redefine this category to the more objective name of Natural Metals. On one hand, Natural Metals is a more accurate description—on the other, we’ll all miss the mysterious charm that the word “exotic” brought to mind.

Exposed Fastener Roof: This is a metal roof that is secured by fasteners (it’s OK to call them screws), which are driven through the panel. This type of roof is also commonly known as a Screw-Down Roof, Direct-Fastened Roof, Thru-Fastener Roof or Through-Fastener Roof.

Green Roofing: One of the most difficult terms to define in the metal roofing industry, there’s not a consensus agreement on how to quantify green roofing as it applies to metal. Some people rely on Energy Star ratings, others use guidelines from the Cool Roof Rating Council and for others it may simply be a matter of metal’s recyclability.

Reroof, Retrofit or Roof-Over: These are all somewhat interchangeable, though there are some subtle differences to describe the use of a new metal roof to replace an existing (usually failing) roof. Retrofit can refer to other types of rehab projects like buildings or walls. A Roof-Over means that the new metal roof is installed over the top of the existing roof, without tear-off of the old roof. Reroof implies simply that a new roof was installed, without quantifying whether the old roof was left in place or torn off. We generally use the terms Reroof or Retrofit.

Ribbed Panels: On DesignandBuildwithMetal.com we use this term to refer to virtually any metal panel that is not smooth-faced. While smooth-faced panels are confined to vertical (wall) use, most ribbed panels can be used on roofs or walls.

Standing Seam Roof: Referring to a roof with no thru-fasteners and whose panels are connected at raised seams, the standing seam roof is popular for a wide range of project types. The reason I’m calling attention to it here is because you’re likely to hear references to architectural and structural standing seam systems. While there are varying definitions, a good rule of thumb is that architectural standing seam roofs require a solid deck sheathing (plywood, for example) and are installed at a steeper roof pitch, such as 3:12 or maybe 4:12 or more.

Steelox Roofing: Armco Steel introduced Steelox standing seam roofing many decades ago, so the term Steelox Roofing is often used to describe standing seam roofs—similar to the way Kleenex is used to describe tissues or Xerox to describe photocopies. Today, the Steelox brand is owned by NCI Building Systems.

Tin Roof or Tin Roofing: One of the most frequently-used terms to describe metal roofing. Sometimes it’s used to describe steel roofing and sometimes it literally could be referring to tin roofing. More often, we’ve found that when a person says Tin Roofing they could be describing virtually any type of metal roofing.

Wrinkled Tin: Though it comes off as slightly derogatory to some people in our industry, I find Wrinkled Tin to be one of the more colorful descriptions of metal panels. This term can be used to encompass a wide range of metal panel products. I’ve also heard the term Crinkled Tin, but that’s one’s not very common and I sort of suspect the person was hungry and had thoughts of French fries for their next meal.

This seems like a good place to stop for now. The important thing to remember is that the precise term isn’t always necessary to communicate. What’s most important is that we have some common ground.

For additional information, of a much more technical nature than I’m offering here, be sure to check out our Technical Articles section.

Shawn Zuver is editorial/content director for DesignandBuildwithMetal.com. He has been covering the metal construction industry, including residential and non-residential construction, since 1985. To contact Shawn, call (419) 581-2051 or email shawnz@designandbuildwithmetal.com.

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