How to Choose a Metal Roofing Manufacturer
Quick answer
When choosing a metal roofing manufacturer, look past the logo to what matters: the metal (aluminum resists rust, while most manufacturers make steel), a genuine transferable lifetime warranty, independent testing and code approvals (UL 2218, Class A fire), concealed-fastener engineering, and whether the maker stands behind installation through certified installers. The model matters as much as the panel.
What makes a good metal roofing manufacturer?
Not brand size or advertising — the things that determine how your roof performs for the next 50 years. A good manufacturer uses quality metal, backs the product with a real transferable warranty, can prove its performance with independent testing and building-code approvals, engineers out the common failure points (like exposed fasteners), and takes responsibility for the finished, installed roof rather than just shipping panels. Judge manufacturers on those fundamentals, and the biggest name is not automatically the best choice.
Aluminum vs. steel: most manufacturers make steel
This is the distinction most shoppers miss. The majority of metal roofing manufacturers produce steel, which is stiff and economical but relies on a zinc or Galvalume coating that can eventually corrode at cut edges and scratches — and many steel warranties restrict coastal use. Aluminum manufacturers are fewer, and aluminum's advantage is fundamental: it contains no iron, so it physically cannot rust, making it the superior choice for coastal, wet, and long-life applications. Interlock is an aluminum manufacturer, which is why its roofs carry no rust risk anywhere, including on the coast.
What to verify before you buy
Get specific. Ask for the actual warranty document and confirm it is transferable and lifetime, and read what it covers (finish, system, wind, hail). Ask for independent certifications, not marketing claims: UL 2218 Class 4 for hail, Class A for fire, and code evaluation reports (such as ICC-ES or state approvals). Confirm the system is concealed-fastener, since exposed screws are the number-one long-term leak source. And look for an established track record and real, visitable local projects. A manufacturer that can produce all of this is one you can trust for the life of the roof.
Manufacturer and installation: who is accountable?
A roof is only as good as its installation, so the best manufacturers do not just sell panels — they stand behind the installed system through certified installers. That single-accountability model matters: if the manufacturer trains and certifies the crew, one party is responsible for both the product and the workmanship, and the warranty reflects it. Buying panels from one company and hiring an unrelated roofer to install them splits that accountability and can leave warranty gaps. Interlock uses a factory-direct, certified-installer model for exactly this reason. Our guides on choosing a contractor and finding a manufacturer near you go further.
Frequently Asked Questions
Who are the best metal roofing manufacturers?
Rather than a single "best," look for a manufacturer that checks the fundamentals: quality metal (aluminum for rust-proof longevity), a transferable lifetime warranty, independent UL 2218 Class 4 and Class A fire certifications, a concealed-fastener system, and accountability for certified installation. A maker that meets all of those is a strong choice regardless of how large its advertising budget is.
Should I choose an aluminum or steel roofing manufacturer?
For longevity and especially for coastal or wet climates, an aluminum manufacturer is the stronger choice — aluminum cannot rust and needs no protective coating to survive, unlike steel. Steel can suit budget-driven or specific applications, but if you want a rust-proof lifetime roof, choose a maker that specializes in aluminum, such as Interlock.
Does the roofing manufacturer also install the roof?
Some do, through certified installers, and that is the model to prefer — it puts one party behind both the product and the installation, with a warranty to match. Others only sell panels, leaving you to find separate labor. Interlock is factory-direct with certified installation, so the maker of the roof also stands behind putting it on.
Sources
- Metal Construction Association — Choosing a metal roofing system and manufacturer
- The Aluminum Association — Aluminum vs steel roofing
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Last reviewed 2026-07-12 · Reviewed by Scott Plumptree, Director of Marketing