Repurposed Shipping Containers Offer Unique Advantages for the Right Projects

Winter 2022/2023 Issue
By: Tom Gresham
Trinity Buoy Wharf is an arts and cultural center in London that includes several workspaces and offices built out of shipping containers.

Flexibility, affordability and durability are among the factors behind their growing use.

George Runkle has worked on repurposed shipping-container construction projects since 2007, and he’s seen the market experience a marked change in recent years. Attracted to the containers’ durability and the accelerated timelines associated with using them in construction, more developers are incorporating them into a variety of projects, he said.

“It’s really gotten busy,” said Runkle, founder of Runkle Consulting, which provides structural engineering services.

Alan Scott, director of sustainability – building science solutions for Intertek, said the repurposing of shipping containers in construction largely was a fringe phenomenon until recent years.

“In the late ‘90s and early 2000s, there was some use of new purpose-built container structures for pharmaceutical manufacturing and other industrial uses because they were quick to build and easy to transport and deploy,” Scott said. “Some of the first notable repurposing projects were low-scale (one- to two-level) assemblies for retail and recreational projects. We are now seeing larger-scale, full-building developments, repurposed containers that are retrofitted and built-out offsite and then [transported and stacked] onsite.”

Today, containers are used for an array of commercial projects. Scott said these can range from the quick deployment of temporary or permanent single-story auxiliary structures, including storage, office expansion, manufacturing, equipment enclosures and other support structures, to larger projects such as low/mid-rise apartments, retail shops, hotels and a variety of commercial office structures.

For those considering containers for a project, there are some crucial challenges and opportunities to understand about a construction method that is becoming less and less unorthodox.

Speed and Longevity

Speed of construction is among the key advantages of repurposed shipping containers.

“We can put a shipping container building up much faster than doing conventional construction and spend minimal time on site,” Runkle said.

In today’s development climate, Scott said the speed of construction with repurposed shipping containers and other modular construction is particularly attractive as developers focus on getting a building up and generating income sooner. Container projects require a smaller crew — invaluable during the current labor shortage — with fewer logistical delays than other projects.

“Similar to new, purpose-built modular construction, repurposed container structures reduce construction schedules and the cost and disruption of construction on urban sites,” he said. “They have the added advantage of a ready-made structure, avoiding building the stout modular box from scratch.”

Formidable resilience to the elements is among the biggest strengths of container buildings once they are in place, Runkle said.

“A shipping container building can take an unbelievable amount of abuse during storm events,” he said. “They are excellent for coastal construction because of this, and inland they can better stand up to storm events such as tornadoes.”

The vast majority of shipping containers are made from corten steel, which resists rust and is highly weldable.

Runkle said shipping container buildings do not degrade over time the way wood frame buildings do, so they better maintain their value.

“Fifty years from now, the building structurally is going to be as good as it was on Day 1,” he said.

Containers also hold advantages over concrete and steel construction approaches.

“Unlike wood framing, a shipping container building doesn’t rot, get infested with termites, and doesn’t lose strength over time like wood does,” Runkle said. “It’s easier than concrete construction, and cheaper than conventional steel construction.”

In addition, Scott said repurposing existing materials — the containers — for structural elements rather than creating new materials makes for more environmentally friendly construction, leading to less waste and proving appealing to developers with an eye on sustainability.

Making the Design Work

Aesthetically, Runkle said shipping container projects fit best in “older, industrial-type neighborhoods.” On all the projects Runkle has worked on, the containers were left exposed rather than covered or hidden in some way, he said. Unique costs associated with container projects are the need for skilled welders and a crane to set the containers in place.

A key design challenge is maintaining the structural integrity of the boxes, which typically are eight feet wide with lengths ranging from 10 to 40 feet. Runkle said the narrow width of the containers can “constrain what you’re doing,” making it difficult to create large open spaces without costly modifications. In particular, there are limitations on how many holes can be cut in the long sides of the container, as well as how large they are — limiting the flexibility of the interior design.

When containers can be lined up side by side and doorways or other openings can be easily aligned to connect adjacent boxes, “it’s fairly straightforward,” Scott said. However, “if you’re wanting to make an open office or large suite or something with a lot of lateral communication between the modules, it’s more difficult to cut those size holes when you’re looking at a taller structure. It might take some extra steps to reinforce the box, and depending upon how much you have to do, that’s where it might tip it into, ‘Oh, I might as well just build this from scratch rather than trying to retrofit a box.’ ”

In addition, Runkle said architects largely are limited to stacking containers “the same way they are stacked in storage.”

“The more adventurous you get with the architecture, the more expensive and difficult the structural modifications get to be,” he said. “You can’t get artistic with the architecture without drastically increasing costs.”

Accessing the Containers

In general, Scott said, shipping containers are “a low-cost, readily available commodity.” That availability, of course, can fluctuate — along with prices. Runkle said larger projects often require wrangling containers from multiple providers. Most sources will not have enough containers for the project, he said, and those that do will prefer to hold some for other clients.

Scott and Runkle noted that it was very difficult to find containers during the height of the pandemic-fueled supply chain crisis, and Runkle said he saw prices for a 40-foot container reach approximately $7,500 at one especially challenging time in the market. In contrast, he said prices ranged between $2,900 and $3,200 in September 2022.

“It’s an up-and-down market,” Runkle said. “It varies with the time of year, and it varies with the economy.”

Both Runkle and Scott believe the economics of labor and construction schedules will continue to favor container use in construction, and Scott believes surplus shipping containers should remain plentiful and affordable when supply chain conditions are “typical.”

“The ability should be there to tap them for construction,” he said.

Tom Gresham is a freelance writer based in Richmond, Virginia.