The tire foundation - a technique adopted from Earthship designs - requires about 300 pounds of dirt to be packed into each tire. The tires are a kind of permanent formwork for the dirt and act as giant masonry units, staggered by course. Labor is intensive, but materials are available and the process primitive.
Shoveling, pushing, punching, more shoveling, sledgehammering.The tires plump up to extraordinary sizes and feel like rock upon completion.
To prevent the water issues that the previous wall had we install a french drain from some scavenged pipe and bits of crushed rubble. Ideally we should have at least 6 inches of this above the pipe for good drainage, but are short on rubble. Breaking up more blocks is tiresome and what we feel is a poor use of a solid building material.
Down the street, on a lot where a building once stood many years ago, is a small mound of asphalt. It's hard to guess how many years it's been sitting there, situated very visibly on the corner of the block. In smaller pieces it is perfect for drainage material. So we proceed to clean up the lot while waterproofing our new foundation - another win-win scenario.
Seventy-four tires. Twenty-two thousand pounds of dirt. Thanks to more of our helpers: Lu, Anthony, Connor, Jared, Joe, and Chris.
The room now largely stabilized, we can begin more generous alterations to it. A new walkway forms atop the tire wall, eventually leading to new access to the backyard.