Metal roofs are lightweight, easy to install, and resistant to fire, mold, and pests, making them a good option for homes and businesses. They also have an incredible life span. However, they may experience “oil canning,” which refers to panels that look wavy or distorted. Here’s a closer look at this phenomenon and how metal roofing contractors can prevent it.  

What Oil Canning Means in a Metal Roof

Oil canning affects all types of metal roofing, including aluminum, copper, and steel. Though it typically doesn’t cause functional problems, it often diminishes aesthetic value, making metal roofs look like squeezed oil cans, which is where the term comes from. The effect may be more or less noticeable depending on the color of the roof, the way sunlight hits it, and the angle at which you view it. 

How It’s Caused

Oil canning often occurs during the manufacturing of metal roof panels. The metal may warp during the rolling process, often as a result of deteriorated or misaligned roll formers. It can also occur while perforating, ribbing, or cutting the metal into panels.

It may also happen during installation when panels become twisted or distorted due to overdriven fasteners. Additionally, it can occur when the roof substrate moves or deviates. 

The apexes of metal roofs often receive a great deal of direct sunlight, causing them to reach higher temperatures than the bases. If significant temperature differences occur on the same panel, the metal may expand at the top and contract at the bottom, causing it to warp.

How to Prevent It

Since oil canning most commonly affects wider panels, choose materials that are closer to the minimum width of 1 foot. Higher-gauge metal is more durable and less likely to experience oil canning, so select panels in 22 gauge. Additionally, panels that include ribs, striations, or planks will stiffen the metal to help it stay flat. 

During installation, align the metal panels with the roof’s substrate, using felt, membranes, or slip sheets to ensure they lay flat. This way, they won’t conform to contours in the inner structure. Avoid installing them close together since they expand during warm conditions, which can cause excess pressure and warping. 

When you need durable and dependable metal roofing and siding panels for your projects, get in touch with Dixieland Metals of Alabama. They provide metal roofing materials to contractors throughout Dothan, AL, and the surrounding regions. Call (334) 678-0038 to ask about ribbed or interlocking panels in stock. Visit the website to submit a quote request.