THE WEAPON OF CHOICE
The depth required for a foundation varies in different parts of the country. It ranges from a few feet in pleasant climates to several miles as you approach the Arctic circle. Freezing ground in winter is the primary reason for this variance. Freezing and thawing causes heaving. It is a well-known dictum that heaving is never good unless it is applied to women's breasts or shot puts. No matter where you live, though, if you plan to expand your abode horizontally, you will be required to do some digging.
There are two ways to do this. First, you can hire it done. In which case, Caterpillar tractors with huge blades and back hoes that resemble some long dead monstrosity from the Mesozoic period will stop by one day to make ruts in your yard. They will scarify the carpet of grass you have so diligently cultivated around the house, and will remove the fruit trees you planted three years ago that were supposed to bear cherries this fall. And they will do all this before you have even shown them where you want them to dig.
Take my word for it. You don't need their help. Besides, when you are done with your project you want to have the satisfaction of telling the world that you did the entire job yourself, including the foundation.
With your pride on the line, it would then be unseemly to rent a back hoe or a bulldozer. Sure, it would be fun to ride one of those big monsters, but don't forget the rent for just a few hours is enough to put a down payment on a Harley. Your best bet...the SHOVEL. Perhaps your acquaintance with this versatile tool is no more familiar than that preposterous facsimile that graces the ace of spades. Perhaps, too, you have wielded this instrument with a yeoman's spirit when you turned over the sod to start your vegetable garden. In any case, we all know the shovel. You probably have one in your garage. Go out there right now and pick it up. Feel the smoothness of the long wood handle. Lightly tap your foot on the blade to knock off some of that leftover crud from the last time you scooped the doggie-do. Look closely at the rusty blade and take in the inherent nobility of this instrument of labor. Do you want to use a power tool for this project now? No. Where's the satisfaction? You don't need artificial assistance from motors and engines. You want to pit you and your shovel against the great and elemental Earth!