- Picking the right panel for your project
is very important,
and there are many things that go into that decision,
including location, building design,
local codes, and requirements, look, and more.
Today we are looking into the SMI 2.0"
Mechanical Seam profile and learning about its application,
engineering, installation, and when you should,
and shouldn't use it for your roof.
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What's up guys,
welcome to the Metal Roofing Channel,
I'm Thad Barnette.
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We release metal roofing and metal construction content
every Monday and Wednesday.
In this series, we look at a specific profile
and discuss when you should and shouldn't use it.
Installation requirements, applicable engineering, and more.
Our profile today is the SMI 2.0" Mechanical Seam
standing seam profile.
It's a standing seam mechanical lock system,
which means it's installed with hidden clips and fasteners
on the male leg,
and the female leg is seamed to engage the panel.
It is a maximum 18 inch panel width
when it's formed with steel,
and a maximum 16 inch panel width
when it's formed with aluminum.
It can be formed with 22 gauge to 24 gauge steel,
or 0.40 aluminum.
If you use the same material in a heavier gauge,
or a narrow or width panel, the engineering is still valid.
This panel uses approximately 5 13/16
inches of material to be formed.
Mechanical seam profiles are effective in both steep slope,
and low slope applications.
There are hydrostatic systems,
which means they can hold water and remain weathertight,
as they drain slowly off the building.
The SMI 2.0" mechanical seam can be installed
at slopes as low as a 1/2:12 for steel,
and a 2:12 for aluminum.
If it's being installed below a 2:12 for steel,
you must install sealants per ASTM E 2140.
Another differentiator for this profile,
is that it's a structural panel,
meaning it can be used over purlins
in an open framing application.
We'll talk about some engineering specifically
for open framing later in this video.
We talk about engineering often because it uses actual data
gathered about the exact panel profile,
and ensures that if you install your roof
per those specifications,
you're giving it the best chance possible to perform.
For the two-inch mechanical lock profile,
there's a UL 90 construction number available,
but there are also a variety of engineering specifications
available from tests performed in a laboratory by
Sheffield Metals.
The SMI 2.0" mechanical seam panel has been tested in
steel and aluminum over plywood, B-Deck,
and B-Deck with ISO for UL 580 and 1897 Uplift Testing.
ASTM E 1680 Air Infiltration Testing,
and ASTM E 1646 Water Penetration Testing.
Also, ASTM E 2140 Water Submersion Testing
was performed for steel over plywood.
The panel also is rated for Class 4 impact resistance
through UL 2218, and can be used in a
Class A fire rated assembly via UL 790 testing.
Specific to open framing,
it has Uplift Testing for steel with ASTM E 1592,
and Foot Traffic Testing with Factory Mutual 4471.
FM 4471 says it can take a 250 pound concentrated load.
For projects located in Florida or Texas,
the panel holds both FBC and TDI approvals
when using steel over plywood, B-Deck,
and B-Deck with ISO and an additional TDI
approval for steel over open framing.
This panel is eligible for use
in weathertight warranty projects through Sheffield Metals,
and qualifies for the standard SMI 40 year PVDF paint
warranty, and Galvalume® warranties.
Some upcoming testing for Sheffield profiles includes
finishing HVHZ approvals for Florida,
upgrading some non-engineered profiles to have testing,
and doing even more testing on current engineered profiles.
Stay tuned for updates on those.
This panel is a good choice for steep slope
and low slope applications.
And when we see it, it's almost always commercial.
It's a great choice over open framing,
and it carries a UL 90 rating
up to a four foot purlin spacing.
It's good if you want an engineered system,
are interested in commercial weathertight warranties,
or have a building with hydrostatic conditions.
This panel isn't a great choice
if you have enough slope for a snap-lock profile,
and you don't want to use the extra labor for seaming.
Also the two-inch rib is pretty large,
so in some applications,
it might not have the look you want.
And I would not suggest that for DIY projects either.
Now let's look at how this goes down
on a roof with solid decking.
Make sure to follow the engineering guidelines as to what
deck substrate you can install over, proper clips spacing,
approved accessories, and other additional requirements.
I've already fabricated these panels with a one-inch bend
at the eave and a one-inch box at the top.
But if you want to learn how to do it yourself,
there's a couple links in the description.
On the deck, the panel hooks onto the eave,
is pinned on the box end with a couple of fasteners,
and uses appropriate engineered clips on the male leg,
depending on the material and substrate.
There are multiple types of clips use for various
engineering conditions.
The specific engineering requirements for your project
will determine the appropriate clip to use.
This bead of sealant prevents siphoning of water
at the end of the panel.
The next panel hooks onto the eave.
The female leg is placed over the male leg,
and is seamed together.
There are two kinds of bends,
a 90 degree seam and a 180 degrees seam.
Make sure you know which is required with the engineering,
and I can tell you, most of the time,
it's a 180 degrees seam.
This process is usually completed with a robotic seamer.
I'm using a hand seamer for this example,
but it takes a lot of extra labor to seam
the entire roof with the hand seamer to 180 degrees.
Now hand seamers are good for when putting in
a 90 degree bend at the clip locations.
This accomplishes a fixed point while you're laying panels,
so you can go back and seam the panels with
a robotic seamer later
per the seamer manufacturer's instructions.
By putting that 90 degree seam in over the clip,
it makes it easier for the robotic seamer to finish
the 180 degree seam.
I'm finishing the panel using the 180 degree
hand seamer as an example.
Again, not a typical way to do it
unless there's hard to reach areas or something like that.
Robotic seamers will get a cleaner,
more consistent seam, and are obviously easier
on the installer.
Because the panel is only pinned at the top,
and we use butterfly clips,
which come in two parts and move freely,
it can expand and contract as needed at the eave.
The Sheffield Metals' installation details has a great
Thermal Movement chart that shows
how much of a gap you should leave at the eave,
based on the panel metal, deck material,
and panel length.
Over open framing, there are different set of clips used.
The open framing clip floats the panel
off the purlins approximately a half an inch
to help reduce purlin chatter.
Details for this profile are available at
sheffieldmetals.com.
And those details are recommended for both
commercial and residential projects.
This panel is very popular in the industry
due to its low slope and structural capabilities.
If you want to know more about this panel
or other panels that Sheffield Metals offers,
I'll link their profile page in the description below.
Comment if you have any questions,
subscribe here to the Metal Roofing Channel,
and as always I'm Thad Barnette,
and I'll catch you next time.
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