Category Archives: Recyclables

Cardboard boxes | Box Forts?

Who doesn’t like building a cardboard box fort?! Any respectable fort builder knows that boxes are coveted fort-building materials. Earthships puts them to good use in a less creative, but purposeful way.

In an Earthship, cardboard boxes are used for sealing the gaps along the bottom of tires before being pounded full of dirt. As the tires in the wall are staggered, gaps form below. If the tires are not sealed with cardboard, the dirt will fall out of the bottom gap as the tire is pounded. cardboard-boxes-gold-coast

An average sized moving box will provide two (2) tires worth of packing. Therefore, we will need about 600 or more boxes worth of cardboard!

On this year’s Boxing Day, please consider breaking down and saving boxes to donate to our Earthship. 


Aluminum Cans | Can walls

Many of the walls inside the Earthship are made of concrete. These walls are considered partition walls, since they do not support the roof. They essentially act as dividers between rooms.

One unique feature of these walls is that recycled materials can be used as filler to create a lighter and more durable concrete wall. In the previous post, we explored the use of bottle bricks to create small portals of light into the interior spaces. Some partition walls are better as solid, flat surfaces. The filler in these walls is primarily aluminum cans. The cans are slightly crushed to keep them from sliding out of the concrete.

Because the cans are shorter than bottles, they can be covered over easily creating a smooth wall surface. Alternatively, the bottoms of the cans are sometimes used to create a mirrored mosaic pattern.


What about tin or steel cans? These cans do not work well for wall filler, because they are open on one end and therefore less supportive.

We will need several contractor bags full of aluminum cans.


Used Bottles & Jars | Bottle Bricks

The second most crucial wall building material is concrete.  What makes the concrete walls of the Earthship unique is the addition of recycled glass and plastic bottles in the form of bottle bricks.

Bottle bricks create a network of spaces to create a lighter, more durable wall that also lends itself to artistic expression and ambient natural lighting.

How are bottle bricks made?

Glass bottle bricks are made mostly with, you guessed it, beer bottles or other beverage bottles. The best bottles are straight-sided at least 4 inches from the bottom. Jars, wine and liquor bottles fitting this description also work well and add more design options.  The bottles are cut 4 inches from the bottom. The bottom part is washed and let dry to be used for bricks and the top part is recycled.

After the bottoms dry, two (2) of the bottoms are placed cut-side together and duct taped around the seam where they meet.  This is a completed bottle brick!

Plastic bottles are a little bit easier, only one bottle is cut and placed over another intact bottle and then taped. The bottoms of these bottles are often more interesting shaped and lend themselves well to making flower patterns (as seen in the featured photo above).

Here’s a short video about how the bottles are cut and put together Cutting a bottle brick.

Here is a longer in-depth instructional video Bottle Wall Building.