Warranties for Metal Roofs & Walls – Continuing Education Course

Credit: 0.25 LU/HSW (AIA) or 0.25 CEH (IIBEC)

Learning Objective: Once you have reached a successful execution of this learning program, you will gain confidence in choosing the suitable and proper warranty for your client’s metal roof or wall system.

Please Note: After watching the video and reading the text, click the button at the bottom of this page to take the quiz.

The option to apply for or purchase warranties is a critical component of specifying a metal roof or wall on an architectural project. Warranties act as a key selling point and provide reassurance that the roof or wall system will stand the test of time and won’t degrade due to manufacturer or installation issues.

The three most common warranties for architectural metals that you’ll come across are:

  • Substrate
  • Paint
  • Weathertight

Substrate Warranties on Metal Roofing Systems

A substrate warranty is a guarantee that the base metal (that a paint system is applied to) will not corrode due to rupture, fail structurally, or perforate within the specified terms when exposed to normal atmospheric conditions.

Galvalume Substrate Warranties

One of the most common substrate warranties comes on Galvalume sheet and coil products. While the duration/terms will vary from manufacturer to manufacturer, a typical Galvalume substrate warranty can range anywhere from 15 to 25.5 years.

When you’re looking at the substrate warranties on Galvalume products, there might be more than one because of the different ways a coil can be coated or un-coated. For example:

  • There is often a painted Galvalume substrate warranty, which may also be called “AZ50”
  • There is also often an unpainted (or acrylic-coated) Galvalume substrate warranty, which may also be referred to as “AZ55”


  • Areas subjected constant spraying of either salt or freshwater. Most importantly, coastline areas with marine exposure within the following distances:
    • Coastline with breaking surf within 1500 feet
    • Coastline with large bay within 800 feet
    • Coastline with marsh within 400 feet
  • Areas subject to fallout exposure to corrosive chemicals, ash, fumes, cement dust, animal waste, or it’s decomposition by-products, fallout from copper, lead, nickel/silver mining, refining operations, and carbon black
  • Conditions where corrosive fumes or condensation are generated or released indoors.
  • Areas subject to water run-off from lead or copper flashing, or piping or areas in contact with lead or copper or lumber containing same
  • Mechanical, chemical, or other damage sustained during shipment, storage, forming, fabrication, etc.
  • Failure to provide free drainage of water and failure to remove debris from overlaps and all other surfaces of the sheets or panels
  • Improper rollforming, bending, scouring, or cleaning procedures
  • Slopes of roof or sections of the roof flatter than 1:15

While this list is not all-encompassing, it does outline some common situations that a Galvalume substrate warranty doesn’t cover. Therefore, it’s critical to read every inclusion and exclusion outlined in the warranty provided by the manufacturer.

Aluminum Substrate Warranties

You’ll also see manufacturers offer substrate warranties on painted Aluminum products, which are more suited for saltwater environments then Galvalume products are. They also often have a shorter term than Galvalume warranties and can come with a duration of about 20.5 years or less.


  • Areas subject to fallout exposure to corrosive chemicals, ash, fumes, cement dust, animal waste, or it’s decomposition by-products, fallout from copper, lead, nickel or silver mining, refining operations and carbon black
  • Conditions/circumstances where corrosive fumes or condensation are generated or released inside the building
  • Areas subject to water run-off from lead or copper flashing or piping or areas in contact with lead or copper or lumber containing same
  • Mechanical, chemical, and other damage sustained during shipment, storage, forming, fabrication, during or after erection
  • Slopes of roof or sections of the roof flatter than ¼:12
  • Deterioration to the panels caused directly or indirectly by panel contact with fasteners
  • Failure to perform an annual fresh tap water rinse on pre-painted aluminum located within one mile of a seacoast, saltwater, brackish water, etc.

Again, while this list is not all-encompassing, it does outline some common situations that an aluminum substrate warranty doesn’t cover. It’s critical to read every inclusion and exclusion outlined in the warranty provided by the manufacturer.

Paint Warranties on Metal Roofing Systems

A paint warranty is a guarantee from a manufacturer/paint supplier that the paint system applied to the metal substrate will not degrade to a certain degree within a specific time frame. As an architect or design professional, it’s important to understand the different elements a paint warranty consists of, including how to apply, duration of warranty, environment exclusions, etc., so you can clearly communicate this information to clients.

What Does a Paint Warranty Cover?

Common covered paint warranty items include:

  • Cracking, flaking, or peeling – To the extent that is visible on ordinary outdoor visual observance (this portion specifically refers to paint adhesion).
  • Chalking – Defined as a resin system degradation and loss of adhesion on the paint’s surface that results in a white coating. Most warranties ensure the metal roof or wall system will exceed a specified chalking number (roof and wall panels normally have different specified numbers because the roof will have significantly more UV exposure than walls).
  • Color fade – Occurs when the paint’s pigment breaks down and alters the color, exceeding a specified ASTM D-2244 Hunter Delta E (DE) unit. The amount of fade is determined on a number scale by comparing a sample to the baseline color, and every paint warranty should specify the allotted amount of change in Hunter units over a certain length of time. 
What Does a Paint Warranty Not Cover?

This section outlines the circumstances that would not warrant a replacement of the metal roofing (this list is not all-encompassing; please read the warranty for specific exclusions/inclusions):

  • Fire, deliberate damage, wind damage, or improper handling by installers
  • Foreign substances or chemicals present in the environment and inside of the structure
  • After-the-fact additions to a roof that may affect the chemical make-up, like adhered solar panels, snow guards, etc.
  • Liquid or solid material submersion
  • Altered or sculpted beyond what it was intended for
  • Stored or installed in a way that allows for poor air circulation
  • Exposure to animals or animal waste
  • Complimentary roof products, fasteners, or penetrations that could cause a galvanic reaction and ruin the finish or corrode the metal
  • Using non-standard industry installation details
Paint Warranty Considerations


Keep an eye on the time frames expressed throughout a paint warranty, as they may change depending on the circumstances. For example, on the same exact warranty, chalking may only be covered up to 20 years, fading for 30 years, and adhesion for 40 years. This is normal in the roofing industry because some resins, colors, and paint systems are warranted differently as the materials age, which is often reflected and thoroughly explained in the warranty document. 


For most architectural applications, Kynar 500® or Hylar 5000®, also known as polyvinylidene fluoride (PVDF), paint systems are considered the best, while silicone-modified polyester (SMP) systems are second, and plain polyester is a distant third. However, SMP carries a “longer” advertised warranty. However, it tends to come down to the big bold print up top being marketing and the fine print in the body of the warranty being the substance that needs to be paid attention to.

  • When it comes to SMP and the widely promoted 40-year warranty, this is just for film adhesion. The chalk and fade coverages for these same SMP warranties are usually less than that of PVDF.
  • PVDF paint warranties last 20 to 40 years for film adhesion, depending on the manufacturer. The “color warranty” for chalking and fading on the same warranty is generally offered for only 10 to 30 years and depends on the color.
  • Polyester warranties vary dramatically depending on the quality and generally do not exceed 20 years for adhesion and 10 years for color.  


One of the best questions you can ask is: Is the product I’m specifying warrantable in my project’s environment?

For example, steel/Galvalume usually is not warranted within specified distances from a coast. If you find yourself in this situation, consult with the manufacturer to help you find the best product for your design. Other environmental conditions can impact the ability to get a paint warranty, such as buildings that contain livestock, water treatment facilities, pools, etc.


Some colors fade faster than others; a dark color will remain “darker” longer in Northern Ohio than it will in South Florida. For example, red will fade quicker than beige because brighter colors tend to fade faster than earth tones. The most significant advantage PVDF has over SMP paint systems is that it will hold the color integrity longer. The bottom line is that the metal roof or wall system will fade over time because of weathering and UV exposure, but how much will depend on the type of paint system.

Weathertight Warranties for Metal Roofing Systems

A weathertight warranty is a guarantee from the installer and roofing manufacturer that the roof installed on a commercial structure will remain weathertight for the duration of the warranty. First and foremost, weathertight warranties protect the investment made by the property owner for the roof or wall system. This type of warranty says that if a leak develops in the roofing system due to defects in the material provided, manufacturing defects, ordinary wear/tear by the elements, or the installation contractor’s workmanship, then the manufacturer or installer is financially responsible for all repairs needed to return the roof to a weathertight condition.

These warranties also assure the property owner that the metal roof system is installed to the proven standards and details specified and approved by the metal roof manufacturer.

Weathertight warranties are standard in the metal construction industry, especially in spec-driven or architecturally designed projects. These warranties are also known throughout the industry as weathertightness warranties or water-tight warranties. In addition to roofing systems, weathertight warranties can be purchased for metal wall systems.

The Importance of a Weathertight Warranty

It’s no secret that metal is a more expensive, premium roofing choice, which means it’s also going to be more costly to repair if it fails. Spending the extra money on a weathertight warranty to protect that investment is likely going to be worth it for your clients in the long run.

Most importantly, having that weathertight warranty ensures that what’s on the inside of the property is protected. Whether it’s a school filled with kids, an apartment building housing multiple families, a shopping complex filled with merchandise, or a bank filled with money, the people and items on the inside rely on the protection that a metal roof or wall can provide. That’s why it’s so important to specify a weathertight warranty in your commercial projects.

Common Weathertight Warranty Types


Limited weathertight warranties cover repairs up to the dollar amount paid for the cost of the metal roof materials and installation. For example, if the original roof costs $30,000 for both the materials and the installation, the manufacturer would cover up to $30,000 worth of repairs through the specified timeframe. This is not limited or capped by a single issue if multiple events occur in the duration of the warranty.


No dollar limit weathertight warranties do not come with a dollar limit on liability. If the repairs for an affected roof or wall exceed that of the cost of the materials and installation, then it will still be covered. For example, if the original material and installation cost was $30,000, and it costs $36,000 to fix or replace the roof, the manufacturer/installer will cover the full $36,000 cost.


A side lap warranty covers the panel seams and not the flashing zones. These warranties tend to instill some false confidence for property owners. You can ask for a side lap warranty, but it would also be good to ask for a workmanship warranty or something similar, because, in general, most leaks occur in flashing zones more frequently than they do in the field or seam of a standing seam metal roofing system.


Some warranties have varying levels of coverage, whether it’s a variable timeframe or what products and areas are covered. Just make sure to read the warranty being offered to ensure it provides the desired coverage.


With a pro-rated warranty, the property owner may incur some of the costs of repair or replacement. This essentially means that the manufacturer will pay for the part or aspect of the system that failed.

Final Thoughts

Warranties are a hot topic in the metal construction industry. The best thing you can do as an architect/design professional is to ensure you know the available warranties, communicate various options, and correctly specify the products with the best warranty.


  • Read the fine print on each warranty, specifically the inclusions and exclusions
  • Know the environment your project is in and if it could affect the warranty coverage
  • Ensure the paperwork is correctly filed according to the manufacturer’s timeline
  • When in doubt, call the manufacturer of the metal to ask warranty-related questions