The Rise of Metal Building Systems
By Mark Robins, Senior Editor,
Posted
07/28/2011
They're not just tin boxes anymore
Metal buildings excel in construction ease and speed, structure
life span, lower maintenance costs and energy savings. The designs
of pre-engineered metal buildings, now called metal building
systems, have come a long way. Metal building solutions have
actually been around as early as World War II, and have
continuously grown in popularity since then. Metal building
solutions were first used in the war as storage shacks and
temporary shelters. After World War II, people continued to find
use for metal structures and metal building solutions expanded to
cover many applications other than storage. Today's applications
incorporate custom features, efficient insulation, contemporary
aesthetics and flexible solutions for a wide array of uses and
applications.
"A pre-engineered metal building solution is an intelligent way
to apply standardized components, selected for their fitness to
customer requirements (load, climate, aesthetics, etc.), and their
ability to 'fit up' on the job site," says Pat Bruzzese, vice
president of metal buildings division, Armour Steel Supply,
Hamilton, Ontario, Canada. "It represents a verified analysis that
the candidate design using those components will satisfy applicable
building codes and an economical way to deliver a flexible, but
highly functional, building envelope. Its short build cycle
minimizes financial exposure and seasonal
disruptions like winter."
The metal building industry sells more than 40,000 buildings
annually with 50 percent of the dollar value over 20,000 square
feet. Metal building solutions are preferred for
warehouse/distribution, office spaces, warehouses, industrial,
agricultural, indoor sports and "big box" retail. Their cost and
flexibility advantages make them increasingly popular for strip
malls, auto dealerships, and community buildings like churches,
fitness centers, fire stations and theaters. These structures'
attractive designs and architectural options leave admirers
surprised to learn that they are, in fact, metal buildings.
Today, metal building solutions are utilized by organizations
looking for practical answers to their increasing needs; the most
common need: space. Non-loadbearing walls permit wide clear span
interiors, unobstructed by interior columns.
"Metal buildings' 'sweet spot' is large open space and low-rise
construction (one or two stories), preferably one story," says Wes
Brooker, marketing and development manager, American Buildings Co.,
Eufaula, Ala. "Metal buildings need a certain amount of open space.
Metal buildings aren't good for high-rise construction because of
the way the systems are engineered; they've always been an
excellent low-rise building solution. There are restrictions for
metal buildings once you get above a certain height level."
As an investment, pre-engineered metal buildings are hard to
beat. Today's designs and the ability to customize them give owners
the look they want with the functionality they need. Metal
buildings are adaptable to varying climates and energy-efficiency
requirements. They are durable; steel resists corrosion and decay
better than any other material. Steel frames do not warp or settle
like wood frames. Construction costs are minimized compared to
building with traditional materials such as timber, brick and
concrete. "You can build right through all but the most severe
winter weather, whereas concrete pours can be delayed for weeks by
bad winter weather," Bruzzese says.
A cohesive system
With metal building systems you are literally buying a system,
Brooker says. The primary framing, the secondary framing, and the
wall and roof panels are engineered to work together. "Basically
one third by weight of the building is the primary framing which
are the 'major frames' of the building," he says. "One hundred
percent of it is made from recycled steel which makes the building
very sustainable. It's a great selling feature and it's good for
the ecology.
"The second third by weight is what we call
secondary framing. These frames go in between the main framing and
hold onto wall panels and roof panels. They provide lateral support
for the building staff so it doesn't come down in adverse
conditions. The steel used for this is black steel. The third type
of steel by weight is the wall and roof panels. These are either
galvanized or galvalumed for corrosion resistance. They can be
painted with silicone modified polyester and Kynar fluoropolymer
resins. These panels provide weatherability to the building."
Ease of installation
Metal buildings provide shorter build-out times than other
construction systems. Metal buildings have fewer components
allowing quicker fabrication and shorter erection time. Their
components are fabricated off-site and can be erected in any season
with fewer building trades involved, helping to reduce construction
costs. Metal buildings' structural elements are cut with
state-of-the-art equipment so every piece precisely fits with
adjoining members. This reduces downtime and product waste.
"If you compare it to conventional construction, all metal
building systems bolt together," Brooker says. "There is no
welding. For a large building, it may take eight to 10 weeks to
design and engineer a metal building before we send it for
installation. It only takes two to three weeks to actually
physically produce a big building of 250,000 square feet. This is
usually much faster to install than conventional construction. All
of Costco's buildings are metal building system construction.
Costco knows once the steel is on-site, in 60 days they can do
something inside the building.
"When we ship our metal building systems, everything is there to
install that building including the nuts and bolts, all the walls
and all the framing. The entire building is there so you are not
waiting for pieces or parts to come in. With retail stores, time is
important and many retailers will specify metal buildings."
In addition to early occupancy, early start of business and
early return on investment, the labor to put up a metal building is
reduced. This offers a savings of 30 percent or more over more
traditional construction methods. "The reason is no components are
built or 'poured' on-site … it really is just an assembly process,"
Bruzzese says. "So you don't need a lot of the trades that would be
involved in a traditional building erection, and coordination of
deliveries of different materials and scheduling work crews is
infinitely easier. We would be remiss to make it sound so easy to
erect a pre-engineered metal building that pretty much anyone with
a crane can do it. It is important to have only a qualified erector
put up a pre-engineered metal building. Safety is the first
consideration, quality of the install is next and efficiency is
third, and you need a certified erector to deliver all three."
A significant advantage the metal building industry has over
conventional construction is that it controls the entire envelope,
making adjustments to new tougher energy and lighting standards
easier. "This avoids the 'Keystone Cops' syndrome in conventional
construction where everyone in the supply chain points at someone
else for the envelope not performing," Brooker says.
Another benefit of metal building systems is metal roofs. A
metal roof can last 40 years or more, whereas a conventional flat
roof will only last 10 to 15 years, then it must be replaced.
Conventional roofs require substantial yearly maintenance expense,
but metal roofs require no more maintenance than occasional debris
removal. Once installed, a metal building system's expansion may
only involve removing an exterior wall after extensions of framing
and roof structures are complete.
Greener, more sustainable
Metal building systems are ideal for sustainability and the
environment as steel is the most recycled material on the planet.
Recycled steel reduces mining waste by 97 percent, air pollution by
86 percent and water pollution by 76 percent. Producing steel
through recycling also uses significantly less energy than
conventional steelmaking.
The typical metal building is manufactured from at
least 70 percent recycled steel. At the end of its useful life, 100
percent of a metal building can be recycled into a variety of steel
products including new cars, appliances, buildings and bridges.
Most manufacturers offer white paint finish options that exceed the
LEED Solar Reflective Index requirement of 78 to significantly
reduce cooling requirements and costs. These three factors allow a
metal building to earn maximum points on LEED projects and a
subsequent level of certification.
With regard to sustainability, each metal building is custom
designed and engineered from the ground up, normally resulting in
minimal scrap compared to conventional construction. This results
in metal buildings being typically 30 percent lighter due to the
highly efficient use of steel. Lighter buildings also translate to
less expensive foundations.
Many metal building companies are switching to 100 percent
"cool" paint systems for their roof and wall panels. Cool coatings
have different color pigments that can reflect 50 percent of the
heat that hits a panel back into the atmosphere. This
environmentally friendly cool technology was originally developed
for stealth aircraft in the U.S. Military. These coatings help
generate lower environmental temperatures reducing smog and the
heat island effect.
"I think the most important technologies and improvements are in
the coatings," says Bruzzese. "Not only are there now a seemingly
endless array of colors, textures, etc., to choose from, but they
really do hold up to weathering incredibly well. The life of a
pre-engineered metal building roof is really impressive, and the
high SRI finishes available today are a big advantage for keeping
energy costs down."
Lighter colors do make a significant difference in the heat gain
buildup within a building itself. Cool coatings help reduce the
urban heat zone and reduce cooling costs in hot summer months. "A
school using cool coating pigments versus an identical school that
isn't, can save $10,000 a year in cooling costs," Brooker says.
"This is a major breakthrough. The technology has been around for
eight or nine years, but we are just now starting to discover and
use it."
More and more architects, contractors and designers are
discovering metal building solutions and are growing increasingly
aware of its advantages. Industry insiders predict the metal
buildings market to grow, thrive and ultimately reach unprecedented
levels of activity.