Decommissioned cargo containers recycled into building
Rather than see decommissioned steel cargo containers
sent to steel mills as feedstock, St. Louis, Missouri-based SG Blocks
LLC is converting these 8,000-pound containers in framing systems for
commercial, industrial, military and residential structures.
Among its projects are a command office building at
Fort Bragg, North Carolina and facilities that are being constructed
at a port in Jacksonville, Florida.
“Shipping containers are usually in service for 6 to
10 years,” says David Cross, SG Blocks, business development director.
“Our purpose is to take those containers and, depending upon the requirements
of the project, Value-Cycle™ them into a superior building product, which
requires a minimum amount of energy expenditure.”
Containers, says Bruce Russell, SG Blocks’ managing
director, make for a sturdy building material because they were designed
to be waterproof and withstand the effects of salt and waves at conception.
Moreover, because the cargo has to be delivered intact, containers are
well-maintained while in service.
“The framing from containers is very durable and it
stands up well to hurricanes and earthquakes,” says Russell. “They are
extremely strong and have all the necessary floor systems and structural
elements because they were built to hold 60,000 pounds of cargo – to
resist 15 long tons (2,240 pounds per long ton) traversely and 7.5 long
“The steel itself is Cor-Ten or Weathering Steel –
a better grade of steel to start with,” he adds. “When the buildings
are done right, we are able to give the container another 50 years of
life. This is a very efficient method of building that is safe because
of the inherent strength of the steel. The leftover materials can be
recycled into new steel.
“We are doing a lot of work in hurricane areas, particularly
in areas along the Gulf Coast,” he adds. “We want this building to not
only be standing, but to avoid mold problems – the insulation and drywall
should not get wet.”
One SG Block is the equivalent of one container and
for the Fort Bragg project, 12 blocks were used. Prior to shipment, each
block undergoes rust proofing and is subject to other protective measures.
Worldwide, Cross estimates that there 22 million TEU
(twenty foot Equivalent Units, the measure of containers) in service,
with nearly 1 million new containers being brought into service annually
and about 700,000 being retired.
Because container traffic is thoroughly monitored,
retired containers can be easily shipped to facilities for SG Blocks
to begin the ValueCycling process, along with a report on the maintenance
history of each container.
“Our primary source for containers is ConGlobal Industries,
the largest depot operator in the country,” says Russell. “They have
partnered with us and are very supportive because it keeps their inventories
cleaner and more efficient.
“We prefer to use the 6, 7, 8 and 10-year-old containers,”
he adds. “This is still a new technology and we are in the middle of
doing various tests and assemblies to make sure that all building code
issues are resolved. The construction industry is extremely conservative
and it moves slowly, so it is our job to satisfy them.
“We have several engineers and they are working to
make this a routine product so architects and developers fully understand
what an SG Block’s benefits are and how they fit with building codes,”
“We are in discussions with numerous military bases
and municipalities,” says Cross. “This also offers the advantage of having
a minimal footprint in terms of impact on the environment. They can be
assembled on-site and disassembled to be moved to a new location.”
“At Fort Bragg, it was estimated that the complex would
take 132 days to complete traditionally,” he adds. “With our system,
just installing the modified blocks, no cladding or drywall, reduced
the construction time by 30 percent.”
SG Blocks has created a national distribution system
that is based on ConGlobal, which has facilities on all three coastlines
and in the key transportation centers of Memphis, Tennessee and Chicago.
Using SG Blocks translates into points towards LEED
(Leadership in Energy and Environment Design) accreditation based on
the use of recycled construction materials and reducing the travel distance
for the materials.
“One of our partners is an architectural firm and they
have done a pretty strong analysis for LEED construction,” says Cross.
“We are making our product very friendly for use by the construction
industry and the various sub-trades.”
Furthermore, the framing system can be used in all
climates, be it extreme cold or heat. Russell says that the firm is considering
possibility of using the steel for the construction of bridges, pedestrian
walkways and similar infrastructure.
“It’s just a matter of the engineering and the applications,”
he says, noting that creating sections for buildings with SG Blocks is
similar to pre-fabricated concrete construction. “One of the biggest
problems in the recycling industry is the introduction of new materials
and uses for them. We are trying to make our product understood by the
mainstream of the architectural and building communities.”