Last Updated: Jul 10, 2021
Shipping container homes seem to embody the idea of a sustainable home. The notion of salvaging hundreds of thousands of used shipping containers sitting at ports worldwide and turning them into innovative, modern homes is undoubtedly appealing to sustainably-minded citizens. Recycling and reusing, after all, are two of the three “r´s” taught in grade school. However, as with any housing alternative, there are always certain considerable disadvantages.
We recently spoke with Robert Humble, the founding partner, and design principal from the Seattle-based company Hybrid Architecture. Hybrid started in 2003 as a collaboration of leading Seattle professionals in art, landscape architecture, urban ecology, master planning, and history.
During their beginning years, they were considered pioneers in shipping container home construction. Their Studio 320 is a 2004 project built from two shipping containers delivered just outside the Seattle area. The studio uses reclaimed plywood from old high school bleachers and has been featured on HGTV and the DIY Channel.
Despite their success with shipping container homes, Hybrid Architecture has incorporated a wide diversity of sustainable home concepts to their building portfolio, and today has mostly moved away from an exclusive focus on shipping container homes. Robert says that “our focus today is on sustainable, urban housing that is centered on livability and urban density.”
Robert believes that one of the central tenets of urban sustainability is to “create more density in our urban cores…and to create highly functional environments that work within the specific community.” While shipping container homes might make sense for homeowners, “they don’t fit the bill for every sustainable building project.”
One of the biggest problems with shipping container homes, according to Robert, is that their inflexible dimensions. This can be a problem for urban planning, where building for urban density is a priority. “Since we focus on urban infill,” Robert explains, “it can be hard to maximize the potential of a given lot because containers aren’t flexible when it comes to the dimension of [the] specific lot. If you live in a 20x20 foot lot, you simply can’t use three 8-foot wide shipping containers, and you end up losing space and thus decreasing the urban density possibilities.”
Robert relates that Hybrid Architecture regularly receives phone calls and emails from potential clients interested in building a shipping container home. “I always ask a client why they were attracted to shipping container homes. We get lots of emails from people who are interested in these types of homes because they believe that they will be much cheaper—and the cost of homes in Seattle is so high. Unfortunately, that is not always the case. Shipping containers are expensive to finish, and because they aren’t built in scale (like prefab homes), the construction process tends to be more expensive.”
In the Seattle area, shipping container homes tend to be comparable in cost to other types of homes. “While the container itself might be cheap,” Robert says, “all the finishing work, the foundation, the electrical, plumbing, etc. will be identical in price to a regular house. In addition, the process of building inside a container is difficult. For example, because of the limited interior size of shipping container homes, spray foam has to be used. While this is a great form of insulation, it can be ten times the price of other types of insulation.”
In terms of energy efficiency, Robert explains that “shipping containers initially have zero insulation because it’s just a steel box.” A shipping container that is 8-feet tall, however, would be limited in how much interior insulation you can add. If you reside in a cold climate and want to add a foot of insulation around the interior of the container, you would be severely limiting the interior living space of your home. “In the past, we have insulated inside the container, but we compromised the ceiling height. Now, we focus on a new system insulating outside the container. This allows us to maintain the original interior height and width of the container.”
Another problem that Robert and Hybrid Architecture see with shipping container homes is their overstated sustainability “value.” Shipping container homes do actively address the sustainability ethic of recycling a product and giving it a second use. However, it is not exactly true that there are hundreds of thousands of shipping containers sitting in ports that are just rotting away. “The truth is that shipping companies don’t just throw (the containers) away. They don’t retire them until they’re completely beaten up. So the containers used for housing are the newer ones that could continue to be by the shipping industry. When you get to the nuts and bolts of it, it’s a false prophecy,” Robert believes.
Because of these challenges to building shipping container homes, Robert considers that “there are probably other prefab and systematized solutions that are better suited for urban environments.”
Despite these drawbacks, Hybrid Architecture continues to search for ways to develop a production model that makes shipping container homes more economically feasible for their clients. While maintaining their inherent sustainability value as a recycled product.
“If you can manufacture to scale, shipping container homes can become more cost-effective…We´re trying to develop a system that focuses on using locally sourced shipping containers. We hope that if the assembly can be done in local factories and in scale, it will lower the cost, make inspection easier, and also decrease the environmental cost associated with shipping a heavy container across the country.”
Robert believes that there are several building niches for which shipping containers are naturally suited. “We think that it is possible to use shipping containers to build prefab kitchens or bathrooms on scale, and then ship them across the country for additions to homes.” Also, Robert thinks that shipping containers are an excellent solution for accessory dwelling units (ADUs).
“Depending on the jurisdiction, if you´re under 200 square feet, there is no need for a building permit, so an 8x20 shipping container might make perfect sense in this case for a tiny home or an ADU. Building prefab ADUs in a factory sourced from shipping containers might make for an inexpensive and good solution to housing problems. They are very fast to build, and we can put one together in as little as one day. We´ve had experiences, where we start at 8 am, and end up at 5 pm having a barbecue with the [shipping container ADU] finished.”
Robert believes that shipping container homes might not be a universal solution for all places and contexts. “The real value is that they helped shift the conversation and opened up ideas for new housing alternatives.” He adds, “Shipping containers are always going to be a niche product. They´re cool. We always ask our clients: ´What are your values? Why are you into containers?´ While these might not be a universal solution, they do represent a case study that forces people to think about how housing can be done differently and more sustainably.”
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.