Before we could plant piers in the ground, we had to decide two things: how many, and where. For the first question, I researched both the load capacity of concrete columns of various diameters and the experience of people who have done what we’re doing.
Some folks have supported their 40-foot containers with piers not only at the corners but at several points along the sides. This seemed like overkill, so I settled on a single pier in the center of each long side, in addition of course to the corners. Some sources even say that no support is needed on the sides at all; we split the difference by placing one pier in the center of each long side. We used 12-inch tubes.
The placement of our house in the yard wasn’t a complicated affair. We stood out there, marking flags in hand, and I, standing toward the rear of the yard, asked, “Where do you want it?” Calvin, standing nearest to the road, said, “A little to your left…a little farther…OK, there.” And we stuck the flags in the ground, defining the place where we would spend our Golden Years in our house made of shipping containers.
We used a very-old-fashioned string-and-batter-board method for laying out the corners, and you better believe that for all the checking and double- and triple-checking, we would be nervous about our work until the day the crane came to lift the container onto those columns, which turned out to be 14 months after the first pier went into the ground. (Remember, Clay works in California and is in Mississippi only a few weeks a year.)
There is no shortage of resources online for learning about the 3-4-5 method for making square corners, so I won’t reinvent the wheel here. Just Google “square corners with batter boards and string line” and you find all you need. Here’s a video that helped me a lot; it might be worth a look.
