Metal Roofing — Best Types & Helpful Tips

If you’re looking for a strong, durable, long-lasting roof system with “green” properties, you’ve come to the right place. Metal roofing dates to the 1700s and is an extremely capable roofing material for commercial buildings.

Metal roofs easily can withstand harsh weather conditions—some have Class A fire ratings. They last for decades—up to 50 years and beyond. And, they contain recycled content and can be 100% recycled, savings tons of roofing waste from landfills. In addition, they are aesthetically pleasing. Metal roofing is available in numerous materials, shapes and configurations. Metal roofing even comes in a variety of colors to personalize your roof. 

When building owners want an attractive and long-lasting roof covering, chances are they choose a metal roof. But with so many options to choose from, deciding on the best metal roof for your building can be overwhelming. 

In this article, you will find the following:

I. Types of metal roofing
II. The two main kinds of structures
III. Advantages and caveats around metal roofs
IV. Six tips for choosing a metal roof

I. Types of Metal Roofing

Metal roofing comes in a variety of materials, and each has its pros and cons:

• Steel: Steel is an alloy made from iron and other elements. Steel is one of the most common materials found in commercial construction and is the most recycled material. Compared with other metals, steel is the least expensive. There are three primary steel roof types:
  • Galvanized steel is created with a layer of zinc to protect the inner layer from corrosion. The coating helps extend the life cycle of steel panels. Galvanized steel is the most common steel roofing material.
  • Galvalume^® steel is like galvanized steel but uses a combination of zinc and aluminum. Aluminum better protects against corrosion. It offers better surface protection than galvanized steel, but it’s more vulnerable to scratches.
  • Weathering steel was designed for projects such as bridges. The outer layer is designed to intentionally rust, protecting the inner layer of steel. It’s often used to accent roofs, with the understanding of the rusting process and need for regular maintenance.
• Stainless steel: Stainless steel is used in the sturdiest metal products. It can withstand corrosion and degradation and is specifically designed for extreme weather and temperatures. It has low thermal expansion properties, so the metal won’t expand and contract during temperature fluctuations. It is a high-end metal roofing material, making its cost in line with copper.
• Aluminum: Aluminum metal roofs come highly recommended in coastal areas because of its resistance to salt corrosion compared with other roofing materials. Aluminum roofs often have a painted coating because it’s natural patina over time may not be aesthetically pleasing. The downside to aluminum is its cost. It’s more expensive compared to roofing solutions that use aluminum as a coating. Aluminum is a commodity, so the cost fluctuates with the market. Typically, the cost for aluminum is between steel and copper.
• Copper: The most attractive of all metal roofing options, copper is an increasingly popular metal roof option. The sheen of brand-new copper will patina into a blue-green color over time. Copper is an extremely long-lasting metal that can last longer than other metals. It’s a soft metal, making it the quietest of metal roofing products, but that also means it’s more easily damaged. Copper is one of the most expensive metal roofing materials, but it also lasts the longest. 

II. The Two Main Structures

Low-slope metal roof

Low-slope metal roof systems have slopes less than 3:12 (meaning the roof rises 3 inches for every 12 inches of its horizontal run) and consist of interlocking panels called standing-seam panels that run vertically along the roof surface. 

A standing-seam metal roof system is also referred to as a “concealed” system. The design helps to drain rain and snow, eliminating leaks associated with built-up (multiple layered) roofs. The panels generally come with a painted or clear acrylic finish. For retrofit projects, a subframing system is attached to the existing flat roof surface to provide a minimum slope. 

Steep-slope metal roof

Steep-slope metal roof systems have slopes greater than 3:12 and generally fall into one of two categories—structural or architectural. 

Structural metal roofs are installed over open framing, but they also can be installed over solid roof decks. Structural systems come in various styles, including vertical standing-seam panels (fastened to underlying purlins with hidden clips), or corrugated panels or tiles (attached with exposed fasteners through panels). 

A corrugated metal panel roof system is also referred to as an “exposed” system because the fasteners are exposed. These products overlap or interlock for a watertight fit. 

Architectural metal roofs require a solid substrate—such as a plywood, concrete or metal roof deck--beneath them. Architectural metal roof panels come in a variety of styles, including standing-seam panels, corrugated panels or tiles, as well as a variety of horizontal metal panels. Most architectural metal roofs are coated with a paint finish available in many colors to add an individualized aesthetic to your building. 

Because they have steep slopes, these types of metal roofs accelerate the rate of water run-off, reducing debris, mold and mildew. At the same time, according to the Metal Construction Association, they are less likely to experience staining from acid rain or ultraviolet degradation than nonmetal steep-slope roof systems. 

III. Advantages and Caveats around Metal Roofing

The Pros of Metal Roofing

Metal roof systems offer many benefits, including:

• Longevity. Metal roofs last two to three times longer than other roof systems, according to the Metal Roofing Alliance. In general, you can count on your metal roof to last 30 to 50 years because metal roofs often can be repainted versus replaced.
• Durability: When installed correctly, metal roofs can sustain wind gusts up to 140 mph. They will not corrode or crack. And many metal roofs are impact-resistant. Impact-resistant roofing materials are designed to resist damage from hail, other flying debris and fire. In addition, according to State Farm insurance, you may be eligible for an annual discount on your insurance premium if you install impact-resistant roofing materials.
• Environmentally-friendly: Metal roofs contain up to 95% recycled content and can be 100% recycled. In contrast, most asphalt shingle tear-off waste ends up in landfills—up to 20 billion pounds annually, according to State Farm. Your metal roof will last 30 to 50 years versus an asphalt shingle roof that will last 12 to 20 years, according to the Metal Roofing Alliance. Fewer roof replacements mean less impact on the environment.
• Increased building value: According to a home guide from SFGATE, a Pulitzer-prize winning news agency, a contemporary metal roof can improve resale value by 1% to 6% when compared with an asphalt shingle roof. Additionally, you can recoup an average 85.9% of your costs for a metal roof.
• Safety: Metal roofs will not spark and ignite into flames during a fire or lightning strike.
• Energy-efficient: Metal roofs reflect the sun’s ultraviolet and infrared rays that contribute to roof surface radiant heat. This results in a 10% to 25% reduction in cooling costs, according to State Farm.

Potential Cons of Metal Roofing

Despite metal roofs’ many benefits, they could have some drawbacks:

• Cost: Metal roofs can cost as much as two or three times more than other roofing materials. Although a metal roof system’s life cycle is much longer than other roof systems, investing in a metal roof only may make sense if you plan to stay in the building long enough to enjoy the cost and long-term benefits.
• Noise: Metal roofs have come a long way regarding noise. But they still may be more noisy than other products, depending on the type of roof deck. Adding more insulation sometimes solves the issue, but it increases the overall cost.
• Expansion, contraction and fasteners: Metal roof assemblies attached as large panels are designed to expand and contract as they warm and cool. Exposed and concealed fasteners have varying lifespans. Washers and screws used during installation may degrade and become dislodged over time.
• Color-match inconsistency: If you need to make a repair or add building improvements years after the original metal roof installation, it may be difficult to find an exact match to the existing metal.
• Performance: If water accumulates anywhere on the metal roof because of poor installation workmanship, it can eventually cause serious damage. Low-grade metals also may be thinner gauge and less durable. Some metals rust in certain climates or dent more easily than others during installation or storms. It’s important to partner with a professional roofing contractor to be sure you are choosing the right materials. A trusted, knowledgeable contractor will install your metal roof correctly and may offer a warranty for workmanship.

IV. Six Tips for Choosing a Metal Roof

All types of metal roofs are strong, durable and long-lasting, so which one should you invest in? Following are six tips to help you get the best metal roof installed: 

1. Do your own research to familiarize yourself with galvanized steel, Galvalume, stainless steel, aluminum and copper roofing materials.

2. Know the unique aspects of your building and decide which materials will work for your building’s location and needs.

3. Determine what factors are important to you, including:

4. Make sure your metal roofing product has been tested, labeled and listed with a testing organization such as Underwriters Laboratories, FM Approvals or Intertek to meet rigorous wind, fire and impact-resistance rating requirements.

5. Partner with the right roofing contractor who will install your metal roof correctly. Poor workmanship can be a disaster down the line. Before you spend your money, spend some time to make sure you are hiring a roofing professional. A price too low should raise a red flag. A low bid sometimes means low-quality work. 

Check with your state’s consumer protection agency (www.usa.gov/state-consumer) to make sure your contractor is licensed and insured. Check to see whether the contractor is a member of any local, state, regional or national roofing associations, such as the National Roofing Contractors Association (nrca.net). And ask about worker credentials and whether they are ProCertified^® to install metal roof systems. For more tips on prequalifying a professional roofing contractor, visit www.everybodyneedsaroof.com.

6. Schedule routine roof maintenance to keep your new metal roof in tip top shape. Talk with your roofing professional to set up routine roof checkups. Some metal roofs will need recoating after the finish wears off, and your roofing professional will know when to perform this service. Otherwise, corrosion can occur.

Metal ahead...

When you install a metal roof system, you’ll save money in operating costs while reducing your impact on the ecosystem. Whether your roofing goal is a great return on investment, many years of problem-free performance or taking an environmentally responsible approach, metal roofs make sense.

There are many commercial metal roof system options. When you’re ready to discuss your needs and budget, contact us at 1 -855-955-ROOF and we’ll help make your metal roof installation a reality. We have over 16 years of experience installing metal roof systems that last for decades, which you can check out in our gallery of metal roof installation projects.