The Durable, Cost-Effective Option for Coastal Metal Roofing Projects: Coasteel™
Durable and cost-effective, Coasteel™ is a coastal metal roofing solution designed for projects 300–1,500 feet from the ocean,offering enhanced corrosion resistance, strong wind performance, and long-term value compared to aluminum.
Coastal metal roofing projects come with extra challenges. Contractors need to protect the project from corrosion and harsh conditions while still keeping the job profitable. High winds, salt spray, and breaking surf can all increase liability and raise the risk of costly callbacks.
Sheffield Metals’ Coasteel™ is designed to help solve that problem. Built with a corrosion-resistant 24-guage ZAM® substrate and finished with a premium PVDF coating, Coasteel offers a durable, coastal-ready option that can be more cost-effective than high-grade aluminum. It comes with a 20-year substrate warranty and a 40-year paint warranty.
Coasteel is lower cost than both 0.032 and .040 aluminum and offers the wind performance of 24-gauge steel. If you have a project that’s 300-1500 feet from the coast, don’t want to buy the added costs .040 aluminum, and need stronger wind uplift performance than aluminum, Coasteel is the ideal option.
In this article, we’ll explain what Coasteel is, where it works best, and when it may not be the right fit for a project.
- What Is Coasteel?
- Why Use Coasteel?
- It Carries a 20-year Substrate Warranty and a 40-year Paint Warranty
- It Helps Defend Against Coastal Corrosion
- It Can Be More Cost-Effective Than Aluminum
- It Offers Long-Term Durability
- When Is Coasteel Right for Your Project?
- You Want to Protect Your Profit Margin
- You Want a Modern Aesthetic
- You Need Better Coastal Protection Than Standard Steel
- You Need a Material That Can Meet Project Requirements
- What Are the Best Applications for Coasteel?
- Projects Located 300 to 1,500 Feet From Breaking Surf
- Standing Seam Metal Roofing and Wall Systems
- Projects Near Brackish Water
- When Is Coasteel Not the Right Choice?
- Projects Within 300 Feet of Breaking Surf
- Projects Farther Inland Than 1,500 Feet
- Exposed Fastener Systems
- Flat Roofs or Certain Industrial Environments
- Projects Where the Owner Is Hesitant to Try Newer Materials
- Which Substrate Should You Use?
- FAQs
- Coasteel vs. Other Coastal Substrates
- Coasteel Installation Considerations
- Why Source Coasteel From Sheffield Metals?
- Interested in Sheffield Metals Coasteel?
What Is Coasteel?
Coasteel is a coastal metal roofing 24-gauge steel substrate coated with a zinc, aluminum, and magnesium (ZAM) alloy and premium Sherwin-Williams PVDF paint, available in:
- Regal White
- Dove Gray
- Dark Bronze
- Matte Black
- Silver Metallic
These colors will be stocked and ready for shipment. Plus, any of Sheffield Metals’ 24-gauge colors can be painted with extended lead times.
Coasteel is designed for projects located roughly 300 to 1,500 feet from breaking surf, offering a balance of corrosion resistance, durability, and cost-effectiveness. It comes with a 20-year substrate warranty and a 40-year paint warranty.
Why Use Coasteel?
Coasteel helps contractors bridge the gap between affordability and durability on coastal jobs. Here are a few of the main reasons to consider it.
It Carries a 20-year Substrate Warranty and a 40-year Paint Warranty
Coasteel is backed by a reliable warranty to give contractors and home and building owners confidence that their projects will stand up to their environment. The warranty covers projects located between 300 feet and 1500 feet from breaking surf, and up to the water’s edge of brackish water. Be sure to read the warranty to ensure any exclusions do not apply to your specific project.
It Helps Defend Against Coastal Corrosion
Coasteel’s ZAM substrate combines zinc, aluminum, and magnesium to improve corrosion resistance in harsh environments. Its magnesium content helps protect exposed steel areas, which can improve performance in coastal conditions where standard steel substrates are more vulnerable.
It Can Be More Cost-Effective Than Aluminum
Aluminum is often the go-to choice for coastal environments, but it can be expensive. For projects that do not require aluminum, Coasteel can offer a more affordable option while still providing enhanced corrosion resistance.
If your project is between 300 and 1500 feet of breaking surf and you want great wind uplift performance without the high price point of aluminum, Coasteel is the material for you.
It Offers Long-Term Durability
Coasteel is built for more than just corrosion resistance. The zinc in the substrate contributes to hardness and durability, while the PVDF coating provides strong resistance to chalking and fading. It also offers cool roofing benefits that can help support energy efficiency.
When Is Coasteel Right for Your Project?
Not every coastal project calls for Coasteel, but it may be a strong fit in the following situations.
You Want to Protect Your Profit Margin
Material costs can make or break the profitability of a job. If aluminum pushes the budget too high, Coasteel may offer a way to maintain coastal performance without absorbing the full cost of a premium aluminum system.
You Want a Modern Aesthetic
Coasteel is not just about performance. Because it is available in Sheffield Metals’ PVDF color lineup, it can also help owners and designers achieve a clean, modern architectural look.
You Need Better Coastal Protection Than Standard Steel
Coasteel is a steel substrate that carries a strong 20-year warranty for projects up to 300 feet of breaking surf and to the edge of brackish water.
Salt spray can quickly become a problem for standard substrates like Galvalume in coastal areas. Coasteel gives contractors an option that offers stronger corrosion resistance for that middle ground between inland applications and the most severe coastal exposures.
You Need a Material That Can Meet Project Requirements
On coastal projects, performance requirements matter just as much as appearance and price. Coasteel is a practical option when you need a substrate that has the strength and uplift performance of 24-gauge steel.
What Are the Best Applications for Coasteel?
Projects Located 300 to 1,500 Feet From Breaking Surf
Coasteel is best suited for projects within this range. Projects closer than 300 feet to breaking surf require aluminum, while projects farther than 1,500 feet inland may be better served by a more economical substrate like Galvalume®. The Coasteel warranty DOES NOT cover projects within 300 feet of breaking surf.
Standing Seam Metal Roofing and Wall Systems
Coasteel is a strong fit for concealed fastener standing seam applications where both appearance and long-term performance matter. It can work well on both residential and commercial projects looking for a sleek, modern metal roof in a coastal environment.
Projects Near Brackish Water
The Coasteel warranty does cover projects that are installed up to the edge of brackish water. So while the warranty does not cover projects within 300 feet of breaking saltwater surf, projects within that proximity to brackish water can still consider using Coasteel. This is especially useful for reducing costs when typically, aluminum would be the only option.
When Is Coasteel Not the Right Choice?
Projects Within 300 Feet of Breaking Surf
Coasteel warranties do not cover projects within 300 feet of breaking surf. In these conditions, aluminum is the better choice.
Projects Farther Inland Than 1,500 Feet
If a project is well outside the coastal exposure zone, Coasteel may not be necessary for the application. In many of these cases, Galvalume can be the more cost-effective option and is more readily available in a wider variety of stocked colors.
Exposed Fastener Systems
Coasteel’s warranty does not cover exposed fasteners. It is intended for concealed-fastener standing seam applications.
Flat Roofs or Certain Industrial Environments
The Coasteel warranty does not cover roofs below a 2/12 slope. It also does not apply to buildings where corrosive fumes or condensates are generated inside or near the structure.
Projects Where the Owner Is Hesitant to Try Newer Materials
Because ZAM is still newer to many contractors, architects, and owners than aluminum, some customers may need more education before they feel comfortable specifying it. In those cases, it helps to provide clear information about where Coasteel works best and why it may be a smart alternative.
Which Substrate Should You Use?
The right coastal substrate depends largely on three key project aspects – wind performance requirements, budget, and proximity to the coast.
Choose Coasteel if:
The project is located between 300 and 1,500 feet from breaking surf and you want the cost-effectiveness and wind performance of steel with the corrosion resistance of aluminum.
Choose aluminum if:
The project is within 300 feet of breaking surf. Aluminum is usually the better fit for the most severe coastal environments.
Choose Galvalume if:
The project is more than 1,500 feet from breaking surf and does not require the added corrosion resistance of a coastal-specific substrate.
Put simply:
- Within 300 feet: Aluminum
- 300 to 1,500 feet: Coasteel
- Beyond 1,500 feet: Galvalume
FAQs
Coasteel vs. Other Coastal Substrates
How does Coasteel match up to other substrates designed for coastal applications? Coasteel has a few core differences from other aluminum-alternative coastal substrates on the market:
- PVDF Coating: One way Coasteel separates from other options is its superior PVDF coating, which comes with a 40-year paint warranty and improved chalk and fade resistance.
- 24-Gauge Durability: Coasteel comes in 24-gauge steel, the standing seam standard with testing and engineering provided, while other coastal substrates may come in thinner gauge and be susceptible to high winds.
- Color Variety: Other coastal substrates only come in select colors. Some companies only offer four exclusive colors to choose from. Coasteel comes available in any of our standard 24-gauge colors.
- ZAM Substrate: Other coastal steel substrates use a film layer to improve performance. Coasteel provides a zinc, aluminum, and magnesium alloy, combining all the best qualities of each metal for impressive durability and corrosion resistance.
Coasteel Installation Considerations
- Galvanized clips and screws: Make sure all accessories are compatible to avoid dissimilar metal corrosion.
- Cut edges and penetrations: Be aware to carefully handle any cut edges or penetrations. While the ZAM substrate can help mitigate corrosion on these areas, any exposed penetrations may not be covered by the Coasteel warranty.
- Underlayment: Sheffield Metals recommends Sharkskin Ultra SA for standing seam metal roofing projects, especially in areas with severe weather.
Why Source Coasteel From Sheffield Metals?
Choosing the right substrate is important, but so is choosing the right supplier.
When contractors source Coasteel from Sheffield Metals, they get more than material. They get access to premium PVDF color options, technical guidance, and a team that understands the demands of coastal metal roofing applications.
That support can help contractors evaluate whether Coasteel, aluminum, or another substrate is the right fit based on the project’s location, exposure, and performance requirements. In turn, that can help reduce risk, protect margins, and lead to a better-performing roofing system over the long term.
Interested in Sheffield Metals Coasteel?
Looking for more information on Coasteel? You can also learn more about the substrate behind it in this related article:
What Is ZAM®? Advantages and Best Applications of the Wheeling-Nippon Substrate
If you’re interested in using Coasteel on your next project, contact your nearest Sheffield Metals branch to speak with a sales representative, or fill out the contact form below.
