Metal Roof Warranty Comparison by Manufacturer

The Three Types of Metal Roofing Warranties

Most metal roofing manufacturers issue three separate warranties for each product, and each one covers a different type of failure.

The substrate warranty (also called the perforation warranty) covers the metal panel against rusting through from the underside or topside. This warranty typically runs 20 to 50 years depending on the manufacturer and the coating system. Galvalume steel panels generally carry longer substrate warranties than standard galvanized, and aluminum panels often carry the longest because aluminum does not corrode the way steel does.

The paint finish warranty covers fading, chalking, and peeling of the factory-applied paint system. PVDF (Kynar 500) finishes typically carry 30 to 40 year paint warranties, while SMP (silicone modified polyester) finishes carry 25 to 30 year warranties. The warranty defines specific limits for acceptable color change (measured in Delta E units) and chalk rating. A paint warranty that allows up to 5 Delta E units of color change is standard; tighter tolerances of 3 Delta E are premium.

The weathertightness warranty (sometimes called a system or watertight warranty) is the most valuable and the hardest to get. It covers leaks caused by defects in the roofing system, including both material defects and, in some cases, installation errors. Weathertightness warranties are typically only available when the roof is installed by a manufacturer-certified contractor and range from 10 to 30 years. Not all manufacturers offer this warranty, and some only offer it on their premium product lines.

What Major Manufacturers Cover

Sheffield Metals, one of the largest suppliers of standing seam metal roofing in North America, offers substrate warranties up to 35 years on Galvalume steel panels with PVDF finish and paint warranties up to 35 years for fade and chalk. Their weathertightness warranty is available through their certified installer network and covers 20 years of leak protection when the complete Sheffield system (panels, clips, trim, and underlayment) is used.

McElroy Metal offers similar coverage with substrate warranties up to 35 years, paint warranties up to 35 years on PVDF systems, and a weathertightness warranty of up to 20 years through certified installers. McElroy also offers a unique "Recover" system for metal-over-metal re-roofing with specific warranty terms for overlay installations.

MBCI provides substrate warranties of 25 to 40 years depending on the product line, paint warranties of 30 to 40 years on PVDF, and weathertightness warranties of 10 to 20 years. Their top-tier Signature Series products carry the most comprehensive coverage.

DECRA, the leading stone-coated steel manufacturer, offers a 50-year limited warranty that covers the steel substrate, the stone coating, and wind resistance up to 120 mph. Their warranty is notable for being a single integrated document rather than three separate warranties, which simplifies claims.

Classic Metal Roofing Systems, which specializes in residential metal shingle and shake profiles, offers lifetime limited warranties on their premium product lines. The "lifetime" designation covers the original purchaser for as long as they own the home, with prorated coverage if the home changes hands.

What Voids a Metal Roof Warranty

Reading the exclusions and limitations section of a metal roofing warranty is just as important as reading the coverage terms. Common warranty voids include the following.

Installation by a non-certified contractor voids the weathertightness warranty from most manufacturers. The substrate and paint warranties (which cover manufacturing defects) typically remain in effect regardless of who installs the product, but the weathertightness warranty, which is the most valuable coverage, requires a certified installer.

Contact with dissimilar metals can void the warranty. When copper, lead, or treated lumber comes into contact with steel panels, galvanic corrosion can occur. Manufacturers specify separation requirements for dissimilar metal contact, and corrosion caused by this interaction is explicitly excluded from coverage.

Improper maintenance can void the warranty if the manufacturer's maintenance requirements are not followed. Most manufacturers require annual inspections and timely repair of any identified issues. If a leak develops because a deteriorated sealant was not replaced within a reasonable timeframe, the resulting damage may not be covered.

Environmental exposure beyond the warranty's geographic limitations is another common exclusion. Some manufacturers exclude coverage for panels installed within a certain distance of saltwater, near agricultural operations that produce corrosive gases, or in industrial environments with chemical fallout. If your property falls within one of these exclusion zones, you may need to request a special warranty endorsement or choose a different product line designed for harsh environments.

Cosmetic damage from hail is increasingly excluded from standard warranties, with some manufacturers offering optional cosmetic damage riders at additional cost. This is a response to the rising number of cosmetic damage claims in hail-prone states, where homeowners were filing claims for dents that did not affect the roof's performance.

Transferability

Most metal roofing warranties are transferable to a subsequent owner, but the terms often change upon transfer. A common structure is full warranty coverage for the original purchaser, then prorated coverage for the second owner, with reduced terms. Some manufacturers charge a transfer fee ($50 to $200) and require notification within 30 to 90 days of the property sale.

The transferability of a metal roof warranty adds value at resale because it gives the buyer documented protection on one of the most expensive components of the home. Make sure to pass all warranty documentation, including the manufacturer's certificate, the installer's workmanship warranty, and the original invoice, to the buyer at closing.

How to Compare Warranties Effectively

When evaluating competing bids, create a simple comparison table with the following columns: manufacturer and product name, substrate warranty term and limitations, paint warranty term and Delta E threshold, weathertightness warranty term and requirements, exclusions, and transferability terms.

Pay special attention to the weathertightness warranty. A manufacturer that offers a 40-year paint warranty but only a 10-year weathertightness warranty is providing less overall protection than one that offers a 35-year paint warranty with a 20-year weathertightness warranty. The weathertightness warranty is the one that covers actual leaks, which is what homeowners care about most.

Ask each contractor whether they provide their own workmanship warranty in addition to the manufacturer's product warranty. A good contractor should offer at least a 5 to 10 year workmanship warranty that covers installation errors not covered by the manufacturer. This fills the gap between the manufacturer's warranty (which covers material defects) and the real-world performance of the installed system.