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What Metal Roofing Material Should I Pick?


– What are the different
metal roofing materials? How do I choose which one’s best for me? Which ones work in which environments? We answer all your metal roofing materials and environments questions
on today’s Q&A Monday. (heavy metal music) Welcome to the Metal Roofing Channel. I’m Thad Barnette with Sheffield Metals, and back with me today is Julianne Calapa from our content department. She’s helping me host the episode, and we’ve also got a
familiar face on the show, Tom Southerland. He is back today. Tom, how are you doin’? – Doing good. – Thanks for being on the show. Today we’re talking about
different metal roofing materials and different environments. And so the question that we
got on YouTube comes from Coastal Designs, and they ask: I would like to know what
distance from salt water, ocean front spray versus southside calm, does Galvalume start to
have finish problems? Also, is Galvalume a stronger
roof to use in high-wind coastal areas than aluminum roofs? Given that aluminum roofs
generally cost more than Galvalume roofs, will
the warranty be worth the cost savings? So, there’s a lot of different
parts to this question. I think we should start
with the basics first, aluminum versus steel. So, Tom, can you talk me through what are the main differences
between aluminum and steel, and why you should choose which one? – Well, a pure aluminum
is aluminum all the way through the thickness of the coil. Steel is a, what we use is
Galvalume versus galvanized, but it’s a carbon steel
with a thin coating on it. And in our case of Galvalume
on the painted part, it’s 50% zinc and 50% aluminum. So you do get some
advantages of the aluminum in the Galvalume versus
the straight galvanized. Aluminum also has a lot smoother surface, so it shows imperfections
a little bit more, and it’s probably a little
bit more difficult to paint with the coaters and all. As far as corrosion resistance, with the galvanized, what
you have to worry about is the cut edge or an exposed edge. With aluminum, with it
being a solid material all the way through, you don’t have to worry about the edge rust the
way you do on the Galvalume. – So during installation,
is there different ways that you can try to
avoid those exposed edges to reduce that chance of rust? – Well, you always, and this
would be for any environment you should always turn the ends under when you come to the eve. You need to roll the material
under on itself so that the exposed edge is hidden, is in back. Typically what’ll happen
on Galvalume is that you’ll get the rust and get
a little bit of creepage, but it’ll stop. So if you’ve
got the edge rolled under, you’ll never see it. – It’ll rust, but you’ll never see it. – What about cost wise?
Aluminum versus Galvalume? Which one costs more? Is
there a difference there? – Aluminum is a lot more
expensive than Galvalume, or galvanized right now, but it offsets that a good
bit by the weight factor. So if you’ve got say a
2,000 square foot roof, on steel you’re gonna
need around 2,000 panels to cover that, of product. On aluminum, typically they would consider comparable to 24 gauge in .032 aluminum, which weighs about a little under half the weight of steel. So you’re getting twice the coverage even though it costs a little bit more. It still comes out a
little bit more expensive, but that reduces the
overall cost by a lot. – So what kind of
environment would dictate whether I choose aluminum or Galvalume? Or any other steel substrate? – Definitely the thing that
comes to mind in our industry is a coastal environment. Any time you get on the coast, be it the gulf, or the ocean, any kind of salt water, basically, there is no warranty, paint warranty, for any kind of galvanized, Galvalume, within 1,500 feet. With aluminum, you can get a full, I’m thinking a 25-year warranty, with painted aluminum on the coast. As long as it’s not
extended out over the water. It’s up to the water’s edge. – Is that just because
aluminum doesn’t rust? Or what makes it good in
the coastal environments? – Well, it’s primarily, when
you look at the paintwork, and that’s particularly what
we’re talking about here, paint doesn’t rust. But
what happens is the metal will rust out under the paint, and you’ll have a failure there. The paint’ll start
bubbling and peeling off. With aluminum, it goes back
to what we were talking about before. A cut edge
will not rust on aluminum. It’ll oxidize over, but
that’s a protective barrier, and it doesn’t bubble up
and make the paint release from the surface. – What’s kind of like the
distance where I would feel safe of putting a Galvalume
roof on my house if I was in a somewhat coastal environment? – Well I have seen Galvalume
roofs, painted Galvalume roofs, on the coast, and on the ocean, that have been there for years,
with no problem whatsoever. It kind of boils down to the, you’re not going to get a warranty for it. If you go 1,500 feet in,
you’re going to get a paint warranty, and a substrate
warranty on Galvalume. So if you’ve gotta have a warranty, you’ve gotta go Galvalume
within 1,500 feet, you’ve gotta go more than 1,500 feet for the Galvalume or the galvanized. – And does the salt water
affect the substrate in any other places other than say the exposed edges of Galvalume? – Well we’ve seen issues
around where the fasteners are. So you’re not going to get a warranty, any kind of warranty
on any kind of product that’s with an exposed back. Like a 5V Crimp or any
kind of an R panel or something like that. This only applies to hidden clip systems where there are no exposed fasteners. But when you grill in around… And what happens is, that
fastener’s got a washer on it, and that washer can have
any kind of chemicals in it, I have seen problems and complications from not using the proper fastener. – And you said that
aluminum is a lot lighter than the Galvalume substrate. Is Galvalume stronger than aluminum when it comes to high-wind costal areas? Is that something to keep in mind? – It is. Your Galvalume has a
lot higher tensile strength. And it is gonna be
inherently a lot stronger. The density of aluminum is about
1/3 of what it is on steel. You’ve got a much
stronger product in steel. Now, the aluminum is a lot more malleable. It’s easier to bend and work with. But you can still get good testing and test results with the aluminum. It will not be as good as the steel, but it is sufficient in most areas. Well I guess the only
thing to add in it is that on the aluminum I alluded to
it being a more smooth surface than the Galvalume. And the Galvalume kind
of has pits and peaks and valleys in it. When you coat it, it’s
gonna look like a little bit rougher surface than the aluminum. And the aluminum is easier to vent, and so the imperfections on
the aluminum are going to show up greater than they are on steel, so on the installation
process you need to be extra careful on handling the aluminum, because it is a lot
easier to bend, crease. – Which one is more popular?
I’m assuming it’s Galvalume, but do you get a lot of
requests for aluminum? – Aluminum is I’d say 80%
used on the coast nowadays. So it all depends on where you’re at. Go down to Florida, it’s Galvalume in the middle of the state, and
aluminum on the coast. Kind of like that all the
way up the east coast. It’s getting more popular
on the panhandle and Texas. It’s gonna sweep across
out to the west coast. – So if you want to
learn about this topic, we have a metal roof materials guide that talks about the pros and cons of each metal roofing material, and will kind of help guide you into choosing which material is best for you and your building. Be sure to subscribe to
the metal roofing channel. Thanks a lot to Tom for
jumping on this episode. And shout-out to Coastal Designs again for putting in their comment. If you want your question
answered on Q&A Mondays, comment below, and anything else. Check out Julianne’s blog
on sheffieldmetals.com – Subscribe, too. – Yep, subscribe to the blog. Subscribe to the Metal Roofing Channel, and we’ll catch you next time. (heavy metal music)

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