Corrugated Metal Roofing: Everything You Need to Know Before Buying

Jack Wisniewski
Published янв. 25, 2021
·
9 min read

Corrugated metal roof with a blue sky background

Source: Mullets Aluminum

Metal is the second most popular type of residential roofing option in the United States, according to 2019 data.

Considering the benefits of metal roofing, including longevity, return on investment, and minimal maintenance, this should come as no surprise.

Corrugated panels, one such type of metal roofing, sweeten the deal with superior durability and affordability.

Although corrugated metal roofing is certainly worth a look for these reasons, we recommend considering the costs, potential drawbacks, as well as alternatives before making any buying decisions.

Read on to get a well-rounded take and our recommendations on corrugated metal roofing.

On This Page:

What Is Corrugated Metal?

Diagram with the benefits of corrugated metal

Traditionally, corrugation refers to the distinctive “S” or “wavy” pattern roll-formed into metal sheets. This process gives the metal greater flexibility to bend perpendicular to the ridges while improving stiffness in parallel. In practice, corrugating dramatically increases strength where it matters while maintaining the thin, lightweight profile of metal sheets.

The depth of corrugations impacts the strength of the panel, where a deeper corrugation renders improved strength.

Corrugated metal panels commonly come in ?”, ¾”, ½”, and ¼” sizes, where the value represents the depth of the corrugations. Among these sizes, the ?” panel will provide the greatest structural durability because its corrugations run deeper.

Single-family house with corrugated metal roofing

Image source: McElroy Metal

Today, industry professionals also tend to include ribbed, crimped, and other roll-formed patterns into the corrugated metal definition, as they essentially deliver the same performance.

How Much Does a Corrugated Metal Roof Cost?

Largely depending on the type of material, corrugated metal roofing panels cost around $4 to $15 per square foot. For an average 1,700 square foot roof, you can expect to pay anywhere from $6,800 to $25,500 for a full corrugated metal roof.

A note on calculating how much corrugated metal you need: to seal the seams between each corrugated panel, installers slightly overlap them. This means you will get less coverage per panel than their out-to-out width.

Graphic with the formula on how to calculated the number of corrugated panels needed for a roof

Image source: Corten Roofing

Corrugated metal manufacturers call this the “coverage” of the panel. If you hire a professional roofer, they should take this into account when providing an estimate.

Plan on going DIY? Divide the surface area of your roof by the coverage width of an individual panel. The resulting number will tell you how many panels you need for your project.

Talk to local pros to get quotes on your corrugated metal roof installation project

Corrugated Metal Roofing Cost Factors

Factors that influence costs for any roof installation include the pitch and complexity of your roof, your location, and whether you hire a professional for the job or not.

For corrugated metal roofs specifically, the type and thickness of the metal and the type of paint all play into project costs.

Type of Metal

Types of corrugated metal roofing

Image source: Peterson Roofing

The metal type, which manufacturers call the substrate, largely decides the longevity of a roof. Most homeowners opt for steel or aluminum for their more attractive pricing, although you can also shop for premium materials like zinc and copper.

Metal roofing lifespan figures will vary based on the quality of installation, maintenance, and environmental conditions. Generally, steel and aluminum will last between 30 and 50 years, while copper and zinc can last over 80 years.

We will quickly review the attributes of each metal.

Galvanized Cteel

Galvanized, or zinc-coated, steel is among the most popular bases for its exceptional durability and economical price relative to other metals.

We can further break down galvanized steel based on the thickness of its protective zinc coating, which manufacturers indicate with a numbered “coating weight”.

For instance, heavy-coated G100 steel will resist rust longer than a lighter coated G90 steel. Following suit, G100 galvanized steel will also cost you more than G90 steel.

Exposed steel rusts quickly, so it’s worth investing in heavier galvanized coatings to prolong the life of your roof.

Other types, like galvalume and stainless steel, will run up your bill. However, they take much longer to rust than galvanized steel.

Aluminum

Another affordable option, the foremost appeal to aluminum is that it does not rust like steel – an ideal quality in humid, coastal climates.

Aluminum is also lighter than steel, making it a better metal to use over an existing roofing material. Not only does lightweight aluminum put less stress on the structure, but they also give installers an easier, quicker job.

Zinc

If you never want to pay for a roof replacement again, zinc might be for you. A zinc roof can last beyond 80 years thanks to its natural patina, which protects the metal from corrosion. Many also fancy the distinctive appearance of said patina, which takes on a faint bluish hue.

Zinc roof with windows

However, to savor these benefits, you will need to pay far more than you would for galvanized steel or aluminum.

Copper

Copper sheet for roofing

Image source: Copper Roofing Supply

Copper is as beautiful as it is expensive – very. On top of its unmistakable sheen, the 100-year lifespan of copper stands up to the very best in the roofing space. Copper also patinas to a blue-green color after several years of exposure to the elements, which many agree enhances its appeal.

Metal Thickness

Thicker metal sheets cost more. In return, you receive improved strength.

Roofs without structural sheathing, like those typical of pole barns and post-frame buildings, may need thicker panels. Regions that see harsh weather may also warrant heavier gauge metal roofing to prevent denting and uplifting.

Most homes have solid decking underneath the roofing material that provides structural support. In these cases, panels on the thinner side should suffice.

Keep in mind each material has its own designation for gauge values. Perhaps counterintuitively, a smaller number means a thicker gauge. A 29-gauge panel, for instance, is thinner than a 22-gauge panel.

Metal Paints

Red corrugated metal roof

Image source: Global Home Improvement

If you choose steel, aluminum, or zinc roofing, manufacturers offer different paints to add color and protect the underlying metal. The two most popular coatings are SMP (Silicone Modified Polyester) and PVDF (Polyvinylidene fluoride – often called Kynar or Hylar.)

Both types offer distinct resistances to fading, chalking, and abrasions – common problems with galvanized steel and aluminum exposed to UV radiation. PVDF is considered the premium product and can cost between 15 percent to 35 percent more than SMP.

Concerning energy savings, lighter, more reflective colors can lower your HVAC consumption and qualify for tax credits.

Drawbacks of Corrugated Metal Roofing

Recognizing that corrugated metal roofing is long-lasting, energy-efficient, and relatively affordable when choosing galvanized steel or aluminum, you might begin to wonder why someone would not want it for their roof.

For starters, corrugated metal roofing can develop leaks if not installed and maintained correctly. Corrugated metal also might not look the most attractive. Lastly, corrugated metal is not the most affordable roofing material.

Potential for Leaks

The main problem with corrugated metal roofing stems from the exposed fasteners and seams between each panel – areas where water can leak through.

Even if installers perfectly seal these seams and drive screws correctly, temperature fluctuations over the years will eventually drive the screws out and invite water to seep in.

In turn, proper installation and maintenance are essential to the success of a corrugated metal roof.

Style Can Be Hit or Miss

Ranch with a corrugated metal roof

Image source: Premier Metals

Just as there are reasons to like the look of corrugated metal roofing and exposed fastener alternatives, there are valid points in opposition.

Corrugated metal echoes rural scenes of the countryside for better or worse. The exposed screws interspersed about the surface can detract from the sleek look some homeowners set out for in a metal roof.

We won’t judge your tastes, but bear in mind corrugated metal roofing is arguably not the most aesthetically appealing option in many cases.

Not the Cheapest Roofing Material

While corrugated metal roofing is not necessarily the most expensive roofing material, it’s also not the least. If you want to keep costs as low as possible on your next roofing project, you should stick with asphalt shingles.

However, for long-term savings, you will likely make more return on your investment with a metal roof as they tend to last much longer than shingle roofs before needing a replacement.

Corrugated Metal vs. Standing Seam

To alleviate some of the drawbacks of corrugated metal roofing, many homeowners look towards standing seam metal.

Close up of a standing seam metal roof

Image source: McKinnis Roofing

What’s the Difference Between Corrugated and Standing Seam Metal Roofing?

Exposure of Fasteners and Seams

Close up of a metal roof seam

Image source: Standing seam metal roofs protect the seams between each panel. Source: Building Enclosure

Corrugated metal roofing has exposed fasteners and seams between panels where water can leak through if not sealed and maintained properly.

Standing seam metal roofs, on the other hand, conceal their fasteners and seams. This facet alone effectively eliminates the opportunity for leaks through the roof. Therefore, standing seam roofs last much longer than corrugated metal roofs with even less maintenance.

Style

Rusted metal roofStanding seam metal roof

Image source: Painted Rusted Roofing & Hawaii Metal Roofing Supply

Apart from greater functionality, standing seam metal roofs look sleeker than corrugated metal without screws protruding the surface.

Cost

The most likely reason one might want to stay away from a standing seam metal roof over corrugated metal arises from costs.

A standing seam metal roof costs between $14 and $16 per square foot – a significantly higher price range than their corrugated counterparts and one of the most expensive roofing materials available.

Should You Buy Corrugated Metal Roofing?

Corrugated panels yield a compelling combination of sustainability, durability, and resistance to the elements, among other worthwhile benefits.

Price varies widely depending on the base metal, with galvanized steel and aluminum firmly on the sensible side while zinc and copper both post high barriers to entry. At a minimum, a properly installed and maintained corrugated metal roof should last 30 years.

Corrugated roofing is not perfect, however. We docked points for the exposed fasteners, maintenance needs, and questionable style.

Some other metal roofing systems, namely standing seam, are longer lasting and, in our opinion, more attractive. If you're eager and willing to splurge on your next roof, we recommend considering standing seam metal to make the most of your investment.

Whether you choose corrugated metal, standing seam, or something else entirely, a professional roofing contractor can help you get the ball rolling. See how much your next roofing project will cost in just a few clicks.

Find the best corrugated metal roof installers near me