A modified version of the earthship is built with three concrete walls instead of dirt rammed into old tires. Despite the fact that it uses concrete, an unfriendly environmental material, it has a few advantages over tires and shares most of the earthship advantages.
The previous writings about earthships referred to low-impact, energy-efficient homes originally designed by Michael Reynolds, made from stacked tires filled with dirt, also known as rammed earth, passive solar designed with rain catchment and greywater systems. They are green because not only are they made with recycled materials and natural earth, but they provide extremely environmentally friendly living. The ramming of dirt into the tires makes them very labor intensive but cheap.
The advantages of the tire earthship are:
- it can be built by the owner
- with its thermal mass and passive solar front, it is energy efficient and keeps the home warmer in winter and cooler in summer with a more constant indoor temperature
- it is self-sustainable with rain harvesting, cisterns, and greywater systems to conserve water, greenhouses for food growing areas, and does not strain the environment
- there can be zero electric bills with photovoltaic cells, wind or hydroelectric power generation
- there can be zero water and sewage bills with rain harvesting, on-site processing of runoff water, greywater, and black water with plant beds, and composting toilets
- it makes the occupants more aware of their consumption habits
- it keeps tires out of landfills
- it saves trees
- dirt, tires, bottles and cans are readily available everywhere for building material
- tires provide wind and puncture resistant walls
- it can be free form shapes, more artistic and aesthetically pleasing than rectangle boxes and in harmony with landscapes
- it can be built on cheaper land almost anywhere because it does not need the infrastructure of central grids for energy and water
The disadvantages are:
- it may be harder to sell
- it is very labor intensive ramming earth into tires requiring time and physical strength
- the tires must be well plastered or they will outgas
- the use of tires is illegal in some countries like Belgium so they use sandbags instead
- getting rammed tires approved for building permits is difficult
- getting loans to build an earthship is nearly impossible so you will probably need cash
- as most of them are built in remote or country areas, more fuel is typically used for transporting materials and while living in the home
The differences in a concrete wall earthship are:
- a number one advantage of being approved by building inspectors and for permits, where tire earthships face not being accepted in more regulated regions
- it is more expensive, cost comparable to building a traditional home
- less of it can be built by the owner
- it can be erected more quickly
- it uses earth unfriendly concrete instead of recycling tires and using dirt
- it can be financed
- it may be easier to sell than the tire earthship because it uses more traditional building methods
- it can not be as free-formed shaped.
All of the building system components to make an earthship sustainable can still be included in the concrete wall version. Watch this Planet Green video about one concrete earthship. Watch the documentary Garbage Warrior about earthships and Michael Reynolds' efforts to get them accepted.
In the Greenville, SC area there are several concrete companies such as Concrete Specialties Inc and Action Concrete Contractors Inc. Contact firstname.lastname@example.org for more information on building an earthship in the Carolinas.