By Shawn Zuver, DesignandBuildwithMetal.com
The awareness of metal roofing is undoubtedly at an all-time high, yet I still hear it frequently referred to as “tin roofing". I don't find it to be an offensive reference; instead, it's a reminder of how important language is within the construction
There are specific terms used to describe all parts of a building, from the foundation to cupola, yet virtually every item may have a variety of names that can be used interchangeably. One person’s roof slope is another’s pitch. You say pole
barn, I say post frame.
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, our weekly email
newsletter, ezines and social media accounts. 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 probably the more common term, but hidden clip is also used.
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. This category has been redefined by many people to the more objective
name of Natural Metals. On one hand, natural metals is a more accurate description - on the other, some of us may admit that we miss the mysterious charm that the word “exotic” brought to mind.
Exposed Fastener Roof: This is a metal roof that is secured by fasteners - and 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, because there’s still 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 ability to be recycled or the amount of recycled content used in the finished product.
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 that a new roof was installed, without quantifying whether the old roof was left in
place or torn off. In our postings, 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 both roofs and 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 or OSB, as examples) and are
installed at a roof pitch of 3:12 or steeper.
Tin Roof or Tin Roofing: Mentioned at the start of this article, this is 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 not nearly as common.
I'll pick up with some terms pertaining to walls and buildings in my next posting. In the meanwhile, if you'd like more information on metal roofing, be sure to check the Metal Roofing section of our Supplier Directory.