A secure roof might seem like the finishing touch to building construction, but it is integral to your property. A well-designed and installed roof does more than just protect you from the elements. It helps to maintain energy efficiency and prevents the health issues that can come from damp, mold, and mildew. As such, it is imperative that you make finding the right type of quality roofing for your building a priority.
Over the last several decades, metal has risen to become one of the more popular choices of roof material. But one of the aspects that you need to know before diving into investing here is the potential for longevity. After all, you don’t want to pay for professionals to fit a metal roof only to find that it needs to be replaced every 10 years or so.
So, how long does a metal roof last? Let’s take a closer look at the issue.
The Short Answer
Hildesheim Cathedral in Germany has a copper roof that has lasted since around 1280 A.D. Though most people aren’t going to be looking at a roof they can expect to last centuries, it certainly speaks to the longevity of the material. Using contemporary techniques, it is not unusual for a metal roof to last 40 years, going up to as much as 70 years in some instances.
As is so often the case, there is more that goes into understanding what kind of life span you’re likely to get out of your investment into a metal roof.
Material Matters
When we talk about metal roofing, in most cases we’re not just referring to a single material. Indeed, there are many different types of metal that are suitable to be used on a roof. As such, each will have its advantages and disadvantages when it comes to longevity. This is why giving a single figure for the longevity of a metal roof is not especially accurate — the material you choose will make a difference.
So, what are the characteristics of some popular roof metals that can impact the lifespan?
Steel
This is one of the common materials used for metal roofing. It is one of the more modern types of metal available, as it is made from a composite of different minerals — usually iron, carbon, and a selection of other small amounts of materials like manganese and phosphorus. This alloy is instrumental in making it a strong and durable material to use for roofing. In the event of strong storms or hailstones, it is not especially likely to take the kind of damage that would require repair. Unlike other types of roof — particularly wood — steel is not prone to rotting or mildew, either. It’s also worth noting that steel is a non-combustible, fire-resistant material, so the roof can withstand damage in the case of wildfires or house fires.
A steel roof’s downsides are relatively few, too, when it comes to determining longevity. While it is corrosion resistant to some extent, it is certainly not corrosion-proof. As such, if you’re living in a coastal or high humidity area for a significant period of time, steel might not be the optimum choice. It also tends to be a heavy-weight material and presents some risk of putting stress on the structure of your home.
Aluminum
This has become a popular choice for metal roofing, particularly in industrial spaces, but it can also work for some homes. From a longevity perspective, aluminum happens to be both lightweight and pretty durable. It is a corrosion-resistant material, and as such, it can be exposed to the elements for a significant period of time without a lot of deterioration. If you live in a coastal area, in particular, you’ll find that sea salt will not affect it negatively. The fact that it’s lightweight can also mean it tends to put less pressure on the structure of your property; so there’s less chance of additional damage to your home or underlayment due to weight over the long term.
On the other hand, the lightweight state of aluminum means that it can be prone to denting. If you live in an area of Texas that is prone to heavy hailstones, or other extreme weather, you may find that your roof could get damaged after storms. As such, your metal roof might not be as durable or will require repair sooner than you’d usually expect.
Copper
When people choose copper for a roof material, it’s usually for the aesthetic properties. Once it develops a patina it can gain a classical style. It also happens to be a significant investment. The good news is that, like aluminum, it tends to be corrosion-resistant. Particularly once the patina starts to develop, a protective layer is built up that helps to stave off rusting.
However, it’s important to remember that copper is a soft metal. As such, it is particularly prone to denting. You can get a thicker gauge of copper — which makes the material less likely to dent and warp during extreme weather or falling objects — but the price rises significantly alongside it.
What Could Shorten the Span?
On the whole, metal is a great choice for roofing. But knowing how long a metal roof lasts doesn’t just come down to the material choices. There are relatively few external factors that can impact the potential for longevity. But knowing what these are can not just help inform your choice, but give you direction for maintenance.
Moisture
Some roof materials are resistant to rust and corrosion, but this isn’t the only danger moisture can present to the lifespan of your roof. In homes that don’t have adequate insulation or attic venting, condensation can build up on the inside of the roof. This won’t always affect the roof material itself — though underside corrosion is possible. In most cases, it’s more likely to impact the underlayment, and cause mold and mildew on the walls and structure. As such, it’s important to work with a qualified roofer who can assess your home and help you mitigate these. In many cases, installing a moisture-resistant underlayment can help extend the lifespan.
Failed Seams and Fasteners
Metal roofs obviously don’t tend to come as a single sheet of metal. They’re joined together at the seams, and attached to the structure using fasteners. However, if these have been incorrectly applied or subject to impacts, there could be small gaps in your roofing that can let in rain water or other types of leaking fluid. This is one of the many reasons fitting a metal roof yourself tends not to be a good idea. A qualified roofer can make sure that the fastenings are not screwed off-center, or so tight or loose that they cause gaps in the metal. Indeed, it’s worth having a roofer come out to inspect the metal once a year or so to spot any issues here.
Wrapping Up
In most cases, knowing how long a metal roof lasts comes down to your material choices and making certain a professional installs it. When you choose a metal that suits your climate, you can expect it to last at least 40 years, but in all likelihood, it will be more. Each material comes bundled with its own sets of pros and cons, but there is enough reliable selection that you’re going to be able to find one that lasts decades, wherever you live. This can be extended when you take the responsible steps of having your roof regularly inspected to identify any issues and mitigate additional damage and expense.