Johhny Electriglide wrote:
Plastic. glass, and aluminum cans are used in various walls and ways in Earthship(TM) homes. Usually they are used in a mortar matrix where the strength is from the mortar. This is also usually when recycling centers are far away. Rammed earth tires are the main structure, with mortar and aluminum cans in the voids, and sometimes bottles in the bond beam to pass light room to room, or for decoration. Tires being a big problem to recycle efficiently.
For exterior non-load bearing walls, using plastic or glass bottles to let in light is only for warmer climates. Recycled plastics are also used with sawdust to make deck material and bricks. They are also used as planters or in watering systems for planters.
We use the 3 liter and 1 gallon plastic bottles for emergency water storage and thermal mass.
In solar heated trombe walls (thermal mass), bottles or various capped cans, or even drums, can be mostly filled with water and put in a dark painted mortar matrix. The more thermal mass, the more temperature stability.
I see, so the climate in a particular place should be considered before using plastic or glass bottles and it should compliment the climate. One thing more, I found out that many things can act as thermal mass in the greenhouse, including wood, soil in raised beds, concrete, block, or brick foundations, or even the floor of the greenhouse. But the most effective and least expensive thermal mass is water. Water can store far more heat for a given mass than any other commonly available material. Water is also useful because of its latent heat; it release up a tremendous amount of heat energy as it freezes, and often this is just when greenhouse heat is needed most.