Are All Metal Roofs Created Equal? 8 Factors that Determine Quality
July 5, 2019 | Filed under: Hiring A Roofing Contractor, Metal Roofing Gauge, Roofing Installation, Roofing Materials, Uncategorized
Something is weighing heavily on me these days. It’s the lack of education and depth of knowledge of many, if not most, roofing contractors. I had a contractor send me an email recently and, while I am paraphrasing a bit, here’s what he asked me:
“All of this talk you make about different types of metal roofs seems like hocus-pocus to me, Todd. I’m a contractor, and I know what a steel roof is. All metal roofs are really the same, aren’t they?”
Interesting comments from an industry professional, don’t you think?
Sadly, almost every day I hear from a frustrated homeowner someplace in North America because a contractor installed a metal roof on their home and, in one way or another, it’s not performing.
Here’s an example:
In mid-June, I had a homeowner text me whose house has huge flying gables and the contractor installed an R Panel roof on it with an enclosed gable channel that is trapping every bit of roof debris, ice, and snow – and overflowing with water that is getting into the home.
The fact is, there are many variants available today in metal roofing. And, while early on in our industry (say 30 – 50 years ago), new products were being developed which were better in terms of performance, the trend today is very much toward the development of cheaper products which can be woefully lacking in performance.
And, realistically, there may be justifiable applications for both high and low-quality products. What becomes a major problem, though, is when a homeowner believes they are getting a high-quality product and, in reality, they are getting a low-quality product that is not appropriate for their home and that will leave them frustrated and angry in just a couple of years.
Here’s the Key Question: What factors distinguish high-quality metal roofs from lower quality metal roofs?
It is critical for contractors and homeowners alike to understand the key answers to this question. In answering that, let’s take a look at 8 essential things that need to be thought about concerning metal roof specification.
When considering a metal roof panel regarding any of these things, no assumptions should be made. Again, we see significant downward pressure on price and quality in the metal roofing industry, both from domestic and overseas manufacturers.
Here are the Key Answers: 8 Factors that Determine Metal Roofing Quality
- Fasteners There are lots of things to know about how a metal roof will be fastened, and lots of places where corners can be cut. Are the fasteners exposed or concealed? What is the quality of the fastener? Are they from compatible metal for the roofing be installed? In what ways does how the roof is fastened allow for thermal movement of the metal panels?
- Base Metal Metal type specification is critical to project success. Galvanized steel, Galvalume steel, and aluminum are common. Exotic metals can include copper, zinc, and others. Based on the location of the project, what is the best metal? Things like salt and tropical environments, propensity for acid rain, extreme snow loads, and severe hail are all factors to think about. But, beyond choosing the type of metal, be aware that there are various grades of these metals. Not all galvanized or Galvalume steels are the same. Lower quality products have less zinc on them, and it is the zinc that provides for cut edge protection. Reduce the zinc, and performance is diminished dramatically. In particular, we have seen very low-quality metals being used in metal roofs produced overseas. We also see lower quality steels in the agricultural market often spilling over into residential applications.
- Coating There are two primary paint chemistries used on metal roofs today. They are named for the resin in the paint. Those are Polyester finishes and PVDF finishes. While there are upgraded versions of Polyesters available, their performance beyond about 7 years is very inferior to the PVDF coatings, leading to frustrated property owners. Additionally, some manufacturers play games with the thickness of the paint on their products. Paint costs have been going up significantly, so they have found that less paint allows them to produce a cheaper product, or increase their profits. These “low film” products, though, will erode much more quickly than industry standard finishes will. The other type of typical coating is an aggregate coating, and consumers must be made aware that the stones will wear away gradually over time and that these products can be more susceptible to mildew collection.
- Metal Thickness Metal thickness is largely a component of product design. While understanding the thickness of the metal is never a bad thing, it’s important to keep in mind that more heavily formed products will naturally be made out of thinner metals. This is due to manufacturing constraints in many cases, but it’s also because the forming of the metal builds strength into it.
- Panel Design The “style” of metal roofing goes beyond just aesthetics and fasteners when it comes to product selection. One other key component is whether the panels interlock with one another or just engage. Also, how do the trims work? Do they engage with the metal panels or just rest above or beneath them? Pay close attention to the valleys. Poorly engineered valleys clog with ice, snow, and tree debris, leading to significant roof failure in a few years.
- Warranty There are many things to consider when it comes to product warranties. Who is behind the warranty? Does the warranty cover actual product performance or just the coating? Is it both prorated and transferable? Warranties are legal contracts between the buyer and the seller – they are not indications of performance expectation. Be sure to understand exactly what warranty is being provided.
- Industry Certification The Metal Construction Association (MCA) administers North America’s only independent metal roofing certification program. Their program certifies the quality level of products. I highly recommend only getting involved with products that are MCA Certified Premium Quality.
- Installation I probably should have started with this problem. Proper installation is critical for all metal roof systems. I have always said that I will take an average-grade product that has been installed properly over the best product improperly installed any day! Make sure that you know who will be doing the installation of any metal roof, that they are expertly trained, and experienced.
Now, while the above are all critical things to think about, it’s essential to think about them in terms of the context of the structure upon which the roof will be installed. What do you want to accomplish with the new roof? Is there anything special about the shape of the structure or roof that places particular demands upon product selection, such as the flying gables I mentioned earlier?
As always, know that I am available to be your guide in understanding metal roofing. Feel free to email me whenever I can be of service.
Todd Miller has spent his entire career in the metal building products manufacturing industry. He is president of Isaiah Industries, an organization recognized as one of the world’s leading metal roofing manufacturers. Todd is currently Vice President of the MRA (Metal Roofing Association) and a Past Chair of MCA (Metal Construction Association). Through his website, he strives to raise the bar on standards and practices to provide property owners with the best possible products for successful roofing projects.
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We are trying to get some proof of important Information on why our roof was improperly installed. Not only did it leak the first time it rained. It leaked 5 more times during the winter from ice build up. Each time the contractor fixed it and said they found the reason for the leak it would leak again.
They were actually screwing down the damaged shingles over and over again. The biggest problem here is, the shingles are granite coated interlocking steel shingles with a hidden fastening system.
We wanted new shingles used but they say fastening them with screws is okay because of the manufacturer repair shows on a paper they have that it is allowed.
Our shingles are Energy Loc brand and we cannot get new shingles because the company no longer exists. Do we have a warrenty case?
I asked you earlier about Energy Loc company.
I have never heard of Energy Loc unless it was a private label someone used. There was a company called Dura Loc that is similar to what you explain. I believe unfortunately that, in that case, with the company out of business, there is no warranty coverage. Exposed fasteners is not unusual on stone-coated metal shingles.
Do you have contractor dealers that install your products? I have a colonial style home with red brick veneer on 3 sides. Just increased the gutter size to 6 inches and found large quantity of roof shingle granules in the old gutter. Roof has an 8/12 pitch roof with ridge vents. Do you make ridge vents to match the metal shingle? The color of our shingles are a charcoal gray GAF Product 12 years old and we can see tar shinning through. 24 inch soffit vent all around the house to keep air flow going up the the rake of the roof. Would like to replace roof with a similar color. Very windy
Thanks Dave. There are contractors across the country experienced with the products we manufacture. If you wish, drop me an email at firstname.lastname@example.org and I will let you know who we have near you. We do offer a matching metal ridge vent.
Janet here, from Murrells Inlet SC. 1.5 miles as crow flies from Atlantic Ocean.
Nearly completed a timber pavilion 16′ x 14′ x 9.5 feet high. I intend to have it roofed with black heavy gauge stainless, standing seam, hidden fasteners.
I’ve yet to find a contractor, still doing my due diligence and educating myself with metal roofing products. I’m located in a wind & hail area and sustained hail damage June 2021 which resulted in a complete asphalt shingle roof replacement to the tune of $38,000.
I decided on metal roof, due to the close proximity of the structure to my in-ground pool; no asphalt grits welcome!
My query.. Can you recommend a manufacturer who provides a durable, higher zinc content finish, and your recommendation for a stronger gauge and good quality fasteners?
I’m hoping to achieve my last roof first! I don’t mind spending the extra $$ for a long lasting durable product that will add value to my property. Absolutely do not want flimsy roof panels.
I’m going to run the panels vertically toward my pool; the first 2″x6″x16′ truss at the rear of the structure will be elevated 1. 5″ higher to achieve runoff. I’m topping the trusses with 2’x4″x14′ flat horizontals for a basket weave affect. The roofing will be attached to the aforementioned.
I’m looking for clean, simple lines, a product with optimum performance, long lasting and ascetically pleasing finish.
Your expertise is greatly appreciated!
Thank you very much for your note. I wish you the best with your construction. I want to clarify a couple of things.
You mention “black stainless”. “Stainless steel” is a type of steel with very high chromium content for corrosion resistance. It normally would be silver in appearance for a roofing application rather than painted or coated black in some way. It is also difficult to find stainless run into roofing. Occasionally I see it on some very high end architect-specified projects but only rarely.
The types of steel normally used in roofing are galvanized and Galvalume. Galvanized has a coating of zinc on it for corrosion resistance. Galvalume has a coating of aluminum on it. Both products will usually have a paint finish on them though Galvalume is also available with a clear finish which washes away over a few years.
For a painted product, I’d prefer to see galvanized rather than Galavalume in your application because it offers faster cut edge protection.
Another option would be aluminum roofing which is also normally painted and offers complete corrosion resistance. I normally suggest aluminum for applications within a couple of miles of salt or brackish water.
I do not understand your reference to a “basketweave effect,” etc. Do you have any drawings or photos to represent your intent that you could send to me? My email is email@example.com
As far as manufacturers of aluminum standing seam roofing, I’d suggest Classic Metal Roofing (my company), ATAS, Petersen, or Drexel (the latter two having the same parent company).
Aluminum would be my preference for your location.
Please contact me anytime.