Metal roofing has become synonymous with sought-after qualities like durability, weather resistance, and long-lasting style. Still, even the best roofing systems have some quirks. For instance, an issue sometimes associated with metal roofing is the potential for adjustment noises, or “popping” noises. This is a natural occurrence that can happen during thermal expansion and contraction. Fortunately, this issue does not indicate a structural problem, but it does still deserve some consideration. With proper design, material selection, and installation practices, popping noises can be managed to ultimately ensure that customers can reap the proven benefits of a metal roof with minimal distraction.
A quick physics refresher: Metal expands when heated and contracts when cooled. This movement occurs naturally every day as temperatures rise and fall. Over the course of a year, more extreme seasonal temperature swings create additional movement. The amount of movement depends on the type of metal and the length of the installed panel. For example, a 30-foot aluminum panel may move nearly seven-sixteenths of an inch during a 100-degree temperature change. A steel panel of the same length may move about one-quarter of an inch.
This movement is natural and expected, but it can lead to noticeable side effects. Some building owners report occasional popping or creaking sounds. These noises occur as the metal adjusts to temperature changes and settles, especially during early morning or late afternoon when temperatures are dropping and rising rapidly. Although popping noises can be surprising, they do not indicate a system failure. In most cases, the sounds diminish over time as the roof settles into regular expansion and contraction patterns.
Allowing the metal roof panels to move freely is the key to managing thermal expansion. Floating clip systems or slip joints give the panel space to expand and contract without placing unnecessary stress on fasteners or the underlying structure. Rigidly fastening both ends of a long panel prevents it from moving. Restricted movement tends to amplify stress, noise, and potential deformations.
Roof transitions such as eaves, ridges, hips, and valleys should also be designed with movement in mind. These locations can become stress points if not properly detailed. Equally important, fasteners and clips should not be over-tightened, allowing for the slight movement that is inherent to metal roofing systems. Finally, it’s worth noting that color selection matters – darker finishes absorb more heat than light ones, increasing temperature swings and, by extension, movement. This is why it’s important to balance a project’s aesthetic goals with an understanding of heat absorption and its implications.
No single best practice can totally eliminate popping noises; thermal movement is a natural characteristic of metal. But by understanding how and why this behavior occurs and prioritizing a variety of best practices during design and installation, project teams can reduce the prevalence of occasional noises from the roof. In turn, they can ensure that clients are able to fully enjoy the many performance and aesthetic benefits of a metal roof with minimal distractions.
For project-specific assistance or additional technical guidance, contact your local Drexel Metals representative or our technical services team. We’re here to ensure that your metal roofing system not only meets performance standards but exceeds them.
