What is a Corrugated Metal Panel

Corrugated roofing and siding are widely recognized as the first metal panel profile to be developed and its origin goes back to England in the 1830s. In 1912, Trachte Brothers, Co from Madison, WI designed and patented a roll-forming machine to manufacture corrugated livestock water tanks. In 1919, Arthur Trachte utilized corrugated steel panels to build a structure to house his new Dodge automobile. Arthur’s new garage garnered considerable attention from friends and neighbors, so Trachte started selling garage packages.  In those days, an 8’ x 16’ garage sold for $100. 

From those humble beginnings, a myriad of other roofing and siding panel profiles have been developed that offer different aesthetic appeal, greater strength, and improved weather-tightness. However, the classic appearance of the early corrugated metal panel is still relevant and popular today.  In fact, over the past 20 years or so, the use of corrugated panels has grown significantly as more and more people appreciate the classic and nostalgic appearance of old-style, corrugated panels. 

Corrugated panels are classified as exposed fastener panels, which means they are attached via fasteners that penetrate the panels and attach to the framing or substrate below. The appearance of corrugated panels can vary based on rib height and width.  McElroy Metal offers two corrugated profiles.

Both Multi-Cor and M-Cor feature the classic “wavy” ribs that identify corrugated panels. Multi-Cor’s ⅞” high ribs are more pronounced/bold while M-Cor has a more subtle ½” high rib profile. 

Versatility is another reason corrugated panels are popular. Panels are commonly installed as roofing panels, wall panels, interior accents, and liner panels. 

Manufacturing flexibility is another hallmark of corrugated panels. Due to corrugated panels’ consistent rib configurations, panels can be manufactured in a variety of widths which is dependent on the coil size.  This flexibility enables more options for substrate, colors, and gauges. It is important; however, to note that different panel widths will result in different lap conditions. To illustrate further, let’s take a closer look at 26 gauge Multi-Cor, which can be manufactured out of 41 9/16” or 43” master coil widths. Wider master coil will result in a wider Multi-Cor panel width which will affect standard lap patterns as shown below. 

For more information about laps as well as other information, such as fastener patterns, please see our Multi-Cor and M-Cor Product Data Sheets. 

While the corrugated panel does allow for great flexibility, there are some limitations. For example, the simple, rounded lap does not contain any breaks or gaps that can help prevent leaks by inhibiting capillary draw. Capillary draw is similar to the concept of siphoning, where water can migrate between two layers of metal and result in a leak. Some newer styles of metal roofing, such as McElroy’s Max-Rib, have anti-siphoning drains or channels built into the panel design that helps stop siphoning water. 

To improve weather-tightness, when corrugated panels are installed as roofing, butyl sealants should be applied to all panel laps. Butyl sealants are available in tube form or tape. Please see the images below for an example of how butyl tape sealant is applied.

While corrugated roof panels can be installed over open framing or solid decking, a best practice would be to install over solid decking and a high-quality underlayment, especially for residential applications. 

Corrugated panels have surely withstood the test of time and remain popular today due to their flexibility and a unique, classic appearance.  Although the panel design does have some limitations, proper installation techniques should ensure long-term performance equal to other exposed fastener roof and wall panels.