ArticlesBlog

Engineered vs. Non-Engineered Metal Roofing

Engineered vs. Non-Engineered Metal Roofing


– Welcome back to another Q and A Monday here on the Metal Roofing Channel, I am Thad Barnette from Sheffield Metals – Sorry, I really messed it up. – No, you’re fine. – Delayed response, I am so sorry. (hard rock) – I am Thad Barnette from Sheffield Metals and welcome to another Q and A Monday here on the Metal Roofing Channel. Today I’ve got Julianne Calapa
and Jeff Hock returning, and I’ve got Lori Reynolds on the phone, she’s calling in from Starbucks. How are you doing, Lori? – [Lori] Glug glug glug glug, yum! I’ve got my charger today,
thank you very much! – And Lori is part of
Sheffield’s Technical Department. You wanna tell us a little
bit about what you do at the company and your
industry experience, Lori? – [Lori] Oh, sure. Happy to. For those of you that see me on LinkedIn, my moniker is I period
Love period Metal period. That just about sums it up. But, essentially, for a
couple of decades now, I have been promoting
architectural metal and loving it, and now have my opportunity to do so direct to the architects
and kinda behind the scenes reviewing plans and specs for Sheffield and I’m thrilled to do
it. Great, great company. Every day is a new challenge. – Cool. Well, I’m excited
to have you on, Lori. Today, we are talking
about engineered systems. So, first, Jeff and Lori,
why don’t you tell me a little bit about what
engineered systems are. What makes a system engineered? – Well, an engineered
system is a pedal profile that has been tested over
a certain deck sub-straight or sub-straight period, whether it be a solid sub-straight or open-framing. Tested includes: uplift testing, whichever is applicable
for the deck sub-straight, water penetration testing,
air infiltration testing, could be water submersion
depending on the application, fire raidings, hail
raidings, impact testings, wind-driven rains testing, it all depends on which testing you need per your local building codes. So, an engineered system
is one that has been tested to meet the criteria of
the design for that area. – [Lori] And also, that we
as a company and a culture, hold our products to those standards. You know? And we don’t deviate. – Right. – Yup. That’s a good thing to remember. Because, as a buyer, it’s really important to know, to have that peace of mind that the company that
you’re purchasing from stands behind what they’re selling. They stand behind the tests, so that you can really
build that customer trust. – And you know the product’s gonna perform once it’s been installed on your project, whether it’s a homeowner or
a commercial building owner, you know it’s going to meet
the requirements you put forth. – So is an engineered system more common in a residential? Or a
commercial? Or does it not matter? – Well, you’ll definitely
see more engineered systems in commercial roofing
because you have an architect that has a specification, and that lists all the requirements
that they need to meet. Most homeowners don’t have an
architect for their building, or for their house, so there isn’t really a specification that you need to meet. But, engineering, I believe, is important, whether it’s residential or commercial. You wanna know whatever you’re having put on your house or
building is gonna perform. – [Lori] And I can also share
from a personal perspective, I’ve owned three houses in my life. Three homes that all had metal roofs. Two were on ridge-tops, and
the one I’m in right now is going to be the next evolution that’s going to be engineered. It’ll be better. That’s
all I’m gonna say (laughs). But ridge-tops: a lot of exposure to wind. – What is a ridge-top? – [Lori] Just a higher
point where wind is either coming up from a valley or
down from a higher point, and across your flat part,
which is the top of a ridge, that sometimes continues on
up or goes into a valley. So very, very, unpredictable winds. – And it makes sense to
have an engineered system especially in that application because of that unpredictability. – [Lori] It will. Yes. Yes. Absolutely. – Lori, I’ve got a question
here that someone asked: If a profile is UL listed,
does that mean it’s engineered? – [Lori] No! (laughs) No, it does not. It means it’s UL lifted. And I think I’ll let Jeff take the helm in talking
about construction numbers because I’ve learned how to… really explain this even more but I don’t want to take
the wind from his sail, so he can talk about UL
construction numbers. – I have no sail (laughs). – Take it away! – A UL-90 construction number
is able to be purchased from Underwriters Laboratories
on a specific panel profile. Basically, a lot of
people in the industry all have the same inch-and-a-half mechanical, for example, panel profile. So, instead of everybody
going out and testing it, you can purchase a UL construction number from Underwriters Laboratories. Basically, that number
says, “If you install it “exactly per this this
UL-90 construction number, “then we will say that
you have a UL-90 rating.” There is no engineered stamp that goes on an engineering report,
there is no actual test being done on your product, it’s just, “This panel’s been around so long “if you install it per this, we know “that it should have no
problem meeting UL-90.” But there is no actual
test performance base to back up that statement. Another thing with UL-90
construction numbers is that a lot of times, in the deck construction, they do things that aren’t exactly industry-standard as to
what you would normally see on a normal roof installation. Say it’s over a plywood deck. Usually, you nail down the plywood deck. A lot of these UL construction numbers will require you to use Phillips screws. Or you’ll have to caus
the seams of the plywood where they butt up against each other to stop that air from coming underneath. Those aren’t typical things that people normally do when installing a roof deck. So, a lot of times, those
items are missed when people are installing it per that
UL 90 construction number. So, if you put it on, and you
don’t screw down the deck, and you don’t caus the seams, if it’s a UL 90 construction number, well, that construction
number isn’t valid, because it wasn’t installed
per the construction number. When you have manufacturers
go out and actually test– they test per UL 580,
which encompasses UL 90– but they actually build a test-deck on real world applications,
on how it will be installed in the field, and you get a
true UL 90 engineered system. And then you could take that
further, continuing on to UL 1897, which basically
sees how high of a pressure that panel can reach before it fails. – And is that what kind of testing you’re gonna be doing next week? – That is. We’re gonna be
doing several UL 580 slash 1897 testings along with water
penetration and water submersion. – Can you kinda talk me
through that process? What’s that gonna be like? – For the UL 580 test, we
build a 10 by 10 test specimen based over wood, b-deck, b-deck with iso, whatever sub-straight it is, or assembly it is that
we’re trying to test. And then we actually install it how it would be done in the field. You put down the wood deck, you
nail it off per the spacing. So, in order for that
engineering to be valid you’d have to nail the deck
off per what we tested at, you install the underlayment,
and then you install the panel with the clips
at a certain spacing, depending on what spacing it
is that you require at the time and then they basically try to blow it up and see how high the pressure can get. Once you have all 90 stops– In UL 580 you have UL 30, UL 60, UL 90– once you get all 90 stops, then it moves over to the 1897 testing,
which basically takes it up at a certain increment of pressure, and sees how much it can sustain before it blows off or
has a critical failure. And you don’t use a different
test specimen for each class, you start, it basically
works the panel with positive and negative pressure through UL 30, then that same test specimen
now goes through UL 60, and then that same specimen
goes through UL 90, so it’s been stressed
three different times by the end of the 580 test. So, you’re seeing how it performs, and you’re seeing what it does, where the failure point
is, or if it has any. Obviously, the tighter your clip spacing, the better your panel’s gonna perform because it’s being held down
to the roof deck better. The wider your clip spacing, you have a chance of failing earlier. – And that’s the essence of an engineering system right
there, is that testing. – Right. You’re testing how
the product is to be applied and how it can perform once
it’s installed that way. – Is there a cost-saving
or a cost-difference between a non-engineered
or an engineered system? – You’re not gonna get charged
more for engineered system, Sheffield Metals does engineering, we don’t pass that cost
onto the customers. We provide that as a
service to use our products. Where a cost-increase might come in is clips being put at a certain distance. – Okay. – So, say if it’s a non-engineered system, and the person installing
it puts their clips at three-foot on center,
whereas our engineered system, we put it at two-foot on center. There’s gonna be an increased-cost because you have an increase of materials. But, you also have the peace of mind knowing that if I put my
clips at two-foot on center this is how the panel is gonna perform. If I put them at three-foot on center I don’t know how, it might
perform okay, it might not. I don’t know know because
we didn’t engineer it. Other things is whenever
you do engineering you have to use the same clip
that you engineered with, the same fasteners, so it’s not– well, if I put any clip
at two-foot on center it has to be the clip it was tested with. – Right. When you’ve been testing that system you test it at those
particular increments, so if it’s installed at an
increment greater than that then it’s no longer that
engineered system. That’s correct? – Correct. – So there’s no room for
deviation? It’s that or nothing. – Right. Now you can
have calculations done. Say if you test at one foot and four foot, you can have calculations done to tell you how it would perform at
two foot and three foot, but you need that closest space, and you need that furthest space to be able to come up with how
it will perform in between. – Okay. – I think that brings us
to our last question here– Actually, you had a
question about warranties. – I did. – Why don’t we talk about that first? – So, I wanted to know
what the difference is between the two with warranties in mind. So do they get one warranty
more if they’re engineered? Or less? Or how does that
work? Or does it matter? – We require a minimum UL 90 rating on any of our weather-tight
warranty systems. – Oh, okay. – We don’t warranty systems
that aren’t engineered at all. We don’t do warranties
on residential buildings. – Okay. – And honestly, the main reason for that is: residential buildings
are obviously a lot smaller, we require so many inspections for our weather-tight warranties, – You’d be doing it all day. – By the time you get
there and inspect it, you get back home, it’s done. – Yeah. – So, the commercial buildings
are obviously larger, you have more time to go
out and do the inspections. But, we require a minimum UL 90 rating, even if the specification
doesn’t call for it. You’re gonna install it
at a minimum per UL 90 if you’re doing it with a
tight warranty with Sheffield. – I think that brings
us to our last question: If you don’t provide warranties
for residential buildings or inspect residential buildings, does that mean residential
buildings don’t need engineering? Or should they still consider
engineering as a good thing? – I think every project needs
engineering to some degree. Depending on where–
I mean, whether you’re a commercial building
owner or a homeowner, you still want the same peace of mind knowing that the product
you’re gonna be putting on your building is gonna perform. – Yeah. – Now, to the level of engineering that a commercial
building might need per a residential building? I’m not
saying that they’re the same. But, I will say that, especially
if you’re in a coastal area or in Florida, obviously Florida
has their own set of rules, you definitely want your
building or home engineered per your geographical location. You want to make sure it
can handle the environment, normal and extreme atmospheric conditions that you have in your
area. I live in Florida, we get hurricanes yearly,
so everything in Florida has to be FPC approved at
minimum, for the most part. But, you want to make sure
whatever you’re putting on your palace is gonna perform, and there’s one way to do that, and that’s having an engineered system so you know that it’ll meet
what you’re looking for. If I go up, and I say, “I
think if I put my clips “at this spacing, you’ll be okay.” But I don’t have a test
with a PE stamp on it to back it up, then I
can’t really say that. – And on our installation episode we talked about being
proactive as a building owner. What can you do to
ensure good installation, safe and effective installation, and I think knowing that
your system’s been tested, that it’s an engineered system, that’s a big step forward
as far as being proactive. – Absolutely. Absolutely. – On the front end, not the back end. – Yeah. Yup. – Yeah, you don’t want to find out after your roof’s installed, that, “Oh, by the way, that’s not tested.” – “Just kidding, it might not hold up.” (laughs) – Cool! Well, thanks everybody
for being on the episode, thanks again to Lori and Jeff
from our technical department, thanks to Julianne.
– Thanks! – Check out her blog
on sheffieldmetals.com Subscribe to the Metal Roofing Channel, comment with any questions for
future episodes of Q and A, anything else, like I said,
check out Sheffield Metals online, and we’ll catch you next time! – Thanks.
– Bye! Thanks. (hard rock)

Comment here