Kimberley Mok is a former architect who has been covering architecture and the arts for Treehugger since 2007.

Courtesy of Amos Wheeler and CargoHome, LLC

This shipping container house stacks two to get more living space.

Courtesy of Amos Wheeler and CargoHome, LLC

One of the big advantages of using shipping containers for housing is that they are modular, and manufactured in a way that makes them easy to stack up. Texas-based company CargoHome makes good use of that modularity and stackability in the Helm, a two-story container home that is actually made of a 20-foot shipping container placed on top of a 40-footer, creating a convenient rooftop terrace.

Clad with durable cedar siding that's been spaced out a bit, in order to reveal the surface of the original container, the existing metal doors on the ends have been replaced with full-height glass doors instead to let in more light.

Courtesy of Amos Wheeler and CargoHome, LLC

Due to the constraints of the container, the interior layout on the ground floor is long and narrow, but it manages to fit in a sitting area on one end, a kitchen, dining area and bathroom in the middle, and a bedroom on the far side. The home is insulated and the inside walls covered with pine shiplap, and trimmed in reclaimed barn wood.

Courtesy of Amos Wheeler and CargoHome, LLC

The second storey is accessed via an exterior spiral staircase, which obviously saves some interior space for other uses, but seems a little awkward to be practical on a daily basis (but looking at the company's floor plans, it is possible to get the Helm built with an interior staircase instead).

The top floor includes a nicely done terrace that features a custom-made cable railing system, illuminated with LED lights. Beyond that is the second bedroom and its bathroom. The bedroom doors open directly onto the terrace, expanding the interior space to the great outdoors.

Stacking shipping containers up to create more living space is a good alternative to placing them side by side and cutting structurally-compromising holes in them. In any case, you can either buy a Helm for USD $71,000 and up (depending on options ), or try it out by renting the Helm on Airbnb (prices start at USD $162 and up). To see more, visit CargoHome on Instagram.

Courtesy of Amos Wheeler and CargoHome, LLC

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