Earthship Academy - Week 2

Foundations of Earthship Construction

(Photo courtesy of Charmaine Jones)

Hello!! In this post, I'd like to share some know-how on Earthship construction that I've learned while here at Earthship Academy.

First off, tires form the foundation of Earthship design. Why use tires? Tires are currently one of the world's primary and problematic sources of waste. It is estimated that about 300 million tires are thrown away each year. The rate at which tires are produced in relation to their expendability has resulted in an overwhelming amount of tires in local landfills.

(Source: the Times-Tribune)

 One of the solutions the government Environmental Protection Agency (EPA) has come up with is to burn the tires and cultivate the fumes for fuel. However, while the EPA claims that tire burning neutralizes the toxic chemicals such as benzene, lead, butadiene, and styrene, these claims have not been proven and continue to pose a serious risk for the environment.

Meanwhile, Earthships provide an effective means to repurpose used tires without remanufacturing or chemically decomposing the material. The availability of used tires across the world makes it a great resource for sustainable building construction. This means, Earthships can be built anywhere. One of the benefits in situations where Earthships are hailed for humanitarian and relief efforts is that they can find tires, even in remote places such as the Andaman Islands and the Philippines where it is usually very difficult to ship building materials.

(Photo courtesy of Charmaine Jones)

A conventional model Earthship uses about 1000 tires to create the foundation. When packed with dirt, tires become like durable bricks that provide structural support and thermal mass for the building. Earthships have achieved incredible success in passive solar energy design due to its tire foundation. In fact, the most current Earthship design is able to maintain a constant 72 degree temperature inside the home - naturally - without conventional heating or cooling systems because of its thermal mass.

Another reason why tires are used in Earthships is because of it durability. During a lecture with the creator of Earthships, Michael Reynolds, he explained that even after a forest fire, an Earthship in New Mexico did not burn down thanks to the tire wall foundation. "It's true that a pile of tires, once on fire, is almost impossible to extinguish. Both in the case of rammed-earth tire walls and tire bale walls, there is insufficient oxygen to maintain an ongoing fire and can easily be extinguished." Reynolds showed us a picture of the resulting fire and it displayed the interior and corner of the roof of the Earthship destroyed, but the tire base was still intact! It was a pretty astounding sight and definitely proved the efficiency of tire wall application.

(Photo courtesy of Charmaine Jones)

On this second week of Earthship Academy, I had the chance to work on a tire-brick foundation for a new project. Here is an infographic I created to show the simple process of building a tire wall that anyone can do!:

Step 1: Find used tires with similar dimensions and line the bottom with cardboard. For our build, we mainly used tires that were marked "P235/75R15." However, when the tires weren't marked, we used a measuring tape to find ones that were of similar sizes. Then we used scrap cardboard and lined the tire until the holes were completely covered.

Step 2: Place newly cardboard lined tires in rows on your planned construction site. We lined the tires on our construction site along a straight line which would form the foundation of the building. Now they were ready for the next step, "tire pounding."

Step 3: Fill and pack tires with dirt to make the "tire brick." We prepared buckets of dirt from the mesa and poured them into the tires. A sledge hammer was used to "pound" the dirt into the sides until they were solid and firm.

Step 4: Stack and Stagger tire bricks until a wall is formed! One tip before stacking the tires is to make sure the row of tires are even because sometimes there will be variations in thickness of the tire bricks after they have been pounded. When you've built up the tire wall, you can plaster over it and you can even add a aluminum can or bottle mosaic design!

The possibilities are endless when you use recycled materials...

(Picture of new Earthship Village Ecologies (EVE) building)

Talk to you soon!

-Peace*~!