Container homes — it all started with a spreadsheet

Evolution of llamaBox, December 2016 — March 2017

  • Spreadsheet of construction materials
  • Floor plan, elevations, framing diagrams
  • Talk to city about plans, buildings codes, and energy codes
  • Talk to structural engineers about foundation design
  • Energy calcs for heating and air conditioning
  • Hire PE (professional engineer) to do Manual J and Manual S
  • Revise plans again and again
  • 3D CAD models
  • Search for a building site
  • Search for electricians and plumbers willing to bid the job
  • Find a source for shipping containers
  • Search for a structural engineers again for foundation design (one who will actually talk to me and then actually do the design job)
  • Search for information about how to get a sewer line and water line to the property

It started with a spreadsheet!

Actually, it started with a dream. But really, dreams are b.s. Spreadsheets are where it’s at. You can’t start anything without crunching some numbers first.

The dream did actually happen, back in 2004. I was napping in the hatch of my Bradley on the northeast side of Baghdad and I since the Army uses thousands of conexes (shipping containers) for storage everywhere it goes, I starting wondering if you could build a house out of them. I resolved to do it.

Over the next dozen years, life got in the way. But I had also been learning about construction and real estate through experience in having rental houses and rehabbing houses to flip.

Back to the spreadsheet. By December 1, 2016 I had been voluntarily unemployed for three months, mostly tinkering with web dev and writing content for my DIY home improvement site. It was time to make a list of materials and figure out what this thing would cost.

It was time to make a list of materials and figure out what this thing would cost.

Why use shipping containers? There could be lots of reasons that you might come up with.

  • Cheaper than normal building methods?
  • Portability
  • Modular
  • Hurricane resistance
  • Save the earth
  • Cool factor

I am not yet an expert in all of these, but I originally did have the idea that it might be more economical to build inside a big steel box than the same way home builders have been doing it for decades (what do they know, anyway??).

Also not an expert on home building or hurricane resistance, but here is what I now know based on my entire three months of research and development experience.

Portable and modular

There is no doubt that you can pick up a shipping container, stick it on a truck, and ship it anywhere. That’s the point of containers. If you build a house out of one (or ten), you should be able to do the same thing. Just put some planning into how the pipes and wires fit together so that when you reassemble the house, everything still lights up and the water comes out of the sink.


Pretty sure anything that can be stacked nine levels high and survive a trip across the ocean while protecting 20 tons (millions of dollars) of cargo will be able to withstand a little windstorm. Obviously, after you cut holes in the box to put windows and doors, it is only as tough as those windows and doors. But at least the roof won’t blow off.

Saving the Earth

Building with sticks uses a lot of lumber. But — by using containers you have not eliminated all lumber usage. You can get away with putting studs (2x4 lumber) on 24 inch centers instead of 16 inch centers. That’s 50% fewer 2x4s. Also you don’t have to build a traditional roof structure. You can, but you don’t have to.

Besides reducing lumber usage, you are reusing a gigantic amount of steel that would otherwise be… recycled? Actually I don’t know what happens to containers when they reach end of life, but I’m guessing they don’t get dumped in the ocean. Since repurposing a steel box uses less energy than cutting it into razor blades, let’s chalk one in the enviro friendly column.

Finally, you ARE reducing your square footage from McMansion size 4,000 sq. ft. down to a tiny house size of 320 sq. ft. Unless of course you decided to stack together fifteen of the 40ft. boxes in which case you’re back to destroying the earth like the rest of us.

Cool factor

If it wasn’t enough to be safer from hurricanes and maybe somewhat more environmental, what about style points? I personally gush over the corrugated metal look of these boxes, but if that’s not your thing, you can always style them how you want. For my first project, I’m planning on tacking on reclaimed wood siding to make it blend in with the older houses in the neighborhood.

You can design your house in whatever style you want. The thing is, hardly anyone builds a custom home using containers. My theory is that it’s because no one in America has any sense of imagination. Or it might be that designing custom homes is a lot of work so people would rather customize an off the shelf design.

Now, if there was a shipping container company out there that offered dozens of unique floor plans and exterior styles off the shelf that you could choose from — that might be something people would go for.

Now, if there was a shipping container company out there that offered dozens of unique floor plans and exterior styles off the shelf that you could choose from — that might be something people would go for.

All in all, at least you’re not living in a tract home. You get anti-basic points for that.

Is it cheaper?!?

Sorry to burst your bubble on this, but spreadsheets don’t lie. The resounding answer is … sort of.

For a one-box house (320 square feet), I estimate the materials costs inside the box to be about $21,000 ($65/sf). When all is said and done, I expect it to cost almost $45,000 or $140/sf, which is pretty typical of new construction.

For a larger house the costs seem to drop dramatically. For example, if I were to use two boxes and have a grand total of 640 square feet I would expect to only spend about $7,500 more. That would work out to $82/sf. So you do end up saving some money there.

One thing to note is that I’m talking about costs to build your own. I did factor in almost $10,000 for labor, but not enough to pay a general contractor.