Chapter 1 - Introduction to Engineering Principles for Container Structures

Engineering isn't something many of us think about on a daily basis. In part this may be due to the fact that structural engineers are so good at their job. Ideally the general population isn't even aware that structural engineers exist, much less have much interest in what they do, as long as they do their job well.

If your one of the people mentioned above, here is a quick recap of the structural engineer's role.

It is the structural engineer’s job to assure that our structures are built in a manner that is fundamentally sound. Designed and built with materials that will allow it to safely support itself, it’s occupants, and the occupant’s possessions with minimal risk of failure, even in extreme circumstances such as during earthquakes or hurricanes. Whether at work or at home, our society wants and needs to know that the buildings we occupy are safe, in fact we pretty much take it for granted.

From the engineer’s perspective it makes little difference whether a structure is built of wood, shipping containers or any other material for that matter; his job is simply to assure that the materials used and the structure itself are safe. The engineer’s knowledge of various materials’ strengths and load capacities as well as fire ratings make his knowledge invaluable to the building process.

Among the engineer’s main tasks is assuring that the loads placed upon the building can be supported and that the loads have a path from their point of origin, through the load resisting elements on down to the foundation.

This section is going to explain the basic fundamental difference in load paths between shipping containers and traditional homes as well as how these differences will affect your design and construction assumptions. This is the fundamental knowledge that you will apply in the design and construction phases. An attempt at design and construction without this background information is most likely to result in added expenses and time expended.

To earn a structural engineering degree requiring 4 years worth of schooling, then the graduate is expected to pass a state exam in every states he or she wishes to practice in.   While you or I may not have the knowledge that comes with an Engineering degree (or aspire to it), a good understanding of basic engineering principles will help you in several respects,

The information in this section used along with your copy of the current local building codes will provide you with a solid foundation as you proceed with your shipping container project.

While some writers describe shipping container construction as “Lego for adults” the reality is far more complex than that, unless you simply plan to stack the containers up and live in big metal boxes with no windows and double front doors that weigh about 500 pounds each.  It’s more likely you would want to make some modifications to make your structure more habitable, and your neighbors would probably want you to make it a little more attractive as well. If that is the case you need to read on and get a handle on the ramifications of modifying the shipping containers.

While much has been written about how strong shipping containers are, the reality is that the minute you start cutting openings for doors and windows the inherent strength will be compromised. But by how much? Staggering or cantilevering looks great in the rendering, but will it be safe? These questions cannot be ignored or glossed over, especially if you plan to seek building department approval of you structure, or care about your family’s safety. These safety related issues are actually engineering issues.

One disadvantage of shipping container construction is that the engineering isn't already done for you like it has been for platform and balloon framing methods. The disadvantage of a set of standardized structural tables for the removal of sections of sidewalls, or proper load paths for the overhanging parts of the structure for example, will take time to overcome. but things will get easier, eventually, as the number of container structures grows.

In the meantime use this guide to acquaint yourself with the engineering principles behind a sound container structure and learn how to incorporate these principles, along with your local building codes, into a safe, strong, and structurally sound dwelling for your family.