Metal panel oil canning stands as one of the main reasons homeowners are hesitant to install a metal roof on their home. This upgraded roofing system is an investment, so customers should be aware of the potential product flaws that may come about. Luckily, the pros of metal roofing outweigh the bad. In comparison to asphalt shingles, metal roofs are certainly more of an investment—however, it pays off! Metal roofs remain durable as they face the wear and tear of Mother Nature of the years. Continue reading to learn more about oil canning, how to spot it, and if it can be prevented.
What is oil caning?
If you take a look at a metal roof and notice a wavy, wrinkly, bump-like texture, this roof may have resulted in oil canning. Unfortunately, this is an eventual characteristic of metal roofs. Oil canning occurs in all panel designs, but it’s visibly noticeable in some panel designs more than others. The panel design this phenomenonvisibly affects most is standing seam panels. The flatter the area, the more noticeable the buckling will be. An AG panel has more ridges and valleys distributed amongst the entire panel, so it’s less likely to occur in this design. Metal panel oil canning occurs from stress to the panel over time. This could be from the roll forming process, installation, stress to the decking, and/or the underlayment.
How to spot it
Metal panel oil canning can be easily spotted—depending on the time of the day and where the sunlight is reflecting. Take a look at a metal roof. If you see buckling or waviness throughout the panels, this is metal panel oil canning. Think of how the sun reflects off your windshield when your drive to and from work. Sometimes the light reflects off your windshield making it hard to see, and other times it doesn’t. The sun rises in the east and sets in the west. Your home doesn’t move; therefore, you may notice oil canning at one time of the day more than another.
Is it preventable?
All metal panels are subject to oil canning. Some contractors claim that a larger gauged panel will solve the problem. Unfortunately, this will not solve the issue 100%. Choosing a metal panel with a thicker gauge only minimizes the appearance of metal panel oil canning. All contractors strive for perfection in each metal roof installation they do. However, like all construction projects, nothing is always 100% perfect. The best way to prevent future oil canning is by doing your best to lay the roof upon a smooth foundation. Areputable contractor takes all measures to ensure the underlayment is smooth and free of debris before laying down panels. Supportive elements that make up the home—foundation, beams, frames, etc.—naturally expand and contract over the years from temperature changes. The same concept naturally applies to a roof—oil canning is naturally unpreventable.
Although metal panel oil canning is unpreventable, there are ways you can minimize its appearance. The finish of the panels can reduce the appearance of oil canning. We carry two panel finishes at Wagner Metal Supply—glossy and crinkle coat. The glossy coat is a beautiful finish, but it may highlight oil canning under certain reflections. The crinkle coat isn’t 100% a matte finish, but it reduces the amount of refection the panel gives off dramatically. Choosing panels with a crinkle coat may lessen the appearance of oil canning. Color choice is another way to reduce the appearance of oil canning. Oil canning on dark glossy roofs seems to show up more when the sunrays hit the surface. When choosing a glossy finish, lighter colors are typically less reflective than darker shades.