If you shut off all your mechanical means to heat your home in the winter time at say -25 below, would you find it mildly chilly or would it be completely uninhabitable?
We’ve been in the Pat and Chuck Potter’s Earth bermed Home in Bancroft, Ontario in December under just such conditions so the correct answer would be: “Pass me my sweater it’s getting a bit cool in here.” but that’s about it. I have trepidations as I begin this article mainly because I am somewhat invested in this form of architecture. You see we intend to build one so it’s going to be difficult to write an unbiased post given that I think they’re bloody brilliant, however, I will try to keep my biases in check. Don’t expect any miracles though.
Michael Reynolds started building these things some 30 years ago, and has therefore trademarked the name Earthship under his company, ‘Solar Survival Architecture’. If you consider yourself a visual learner then go to YouTube and check out ‘Earthship on the Weather channel’ for a primer.
If you have more time on your hands rent the documentary, ‘Garbage Warrior’ which chronicles part of Michael’s journey navigating the obstacle course of legal dogma and antiquated building codes as he attempts to work within the system. It also shows in great detail what an Earthship is and how it works.
Rammed Earth Tire Dwellings are generally created as a series of U-shaped walls, built out of earth packed tires placed one row upon each other, strong enough to be load bearing.
The structure needs no foundation to hold it up and is placed directly on the ground to take advantage of geo thermal principles. Later the walls are partially bermed on the outside acting like a beautiful wool blanket from the Hudsons’ Bay Company keeping your home warm in winter and cool in summer. The glass wall of the greenhouse stretches along the entire east/west side of the house which is oriented towards the southern sky. This allows sunlight to enter the structure all day where the planters can benefit, and the substantial thermal mass collects, stores and releases the heat of the day slowly at night when most needed. The interior walls are finished with natural adobe clays or plasters giving it an organic feel, and many room dividing walls use re-cycled glass bottles in the wall itself creating a dazzling ‘stained glass’ effect as the sun shines through the walls and into the spaces within.
While Michael pioneered the concept and continues to refine it in the only Earthship Community that I’m aware of (in Taos New Mexico), rammed earth tire dwellings have begun popping up everywhere on the planet modified to the uniqueness of the area’s geography. Only two main factors prevail overall from one place to another. The foundation is the earth itself so you must be careful to choose a site that doesn’t have a moisture issue. Also, the site must have direct-unfiltered sunlight. You must orient your home passively towards the southern exposure to capitalize on the benefits of the structure’s design. This factor was never more obvious to us then while driving through Vernon, B.C. as we had heard that an Earthship home had been started (but not finished) in the area. As we drove through we understood why. The builders had not observed their ‘site’ through all seasons, and while it must have looked drenched in sunlight during the summer months, here it was at the exact altitude to be floating in the cloud cover during the winter months. Doh! My heart went out to them. A classic newbie mistake. Sit on your land through all seasons and observe the arcing of the sun to see if there will be an ‘obstacle’ to receiving direct sunlight year round is grade A advice.
For the rest of this article I am going to use a phrase coined by Canada’s first ever Earthship owner/builders Pat n’ Chuck Potter when I say that what heats and cools your home is ‘Mass n’ Glass’. Try laying that on your building inspector when he looks for the heating/cooling systems of the house. Once you dig down past the frost line, cover over the back and sides of the home with a nice earth berm wrap, orient your home to receive all the passive heat of the sun, and store that warmth in the mass of dirt filled tires which make up the retaining walls of your structure…your home maintains a year round temperature of approx. 58 degrees. Unlike most homes built above ground your home is regulated by earth stable temperatures not the wildly fluctuating air temperatures that vary from season to season above ground. You think that’s clever, you just wait.
Recycling Grey Water not only makes sense it should be mandatory with the shortages we are starting to experience worldwide. You wash your dishes, your clothes and your body and then all that loveliness goes out to a septic field? What a waste! In this system grey and black water are treated separately using interior and exterior planters which act as the bio filters using the nutrients in the water. Of course you can’t put anything down the drain that would upset the plants which means a change in habits for which products you use. Ultimately ‘greening’ your home can only make for a better more breathable environment for your family.
Where does the water come from? Look up. If they can manage to collect enough water from rain, dew, and snow under desert conditions (Taos, New Mexico is in a desert) then there is enough to go around on this planet if we use it wisely. The roof of an Earthship catches and funnels the water to cisterns buried next to the house. The water is then pumped up and purified to be used and reused. Grey water not only feeds the indoor planters it also goes to the toilet. Why on earth use fresh water to flush? Then again why flush when you can compost but hey…that’s just me.
Since technologies are constantly changing so too are your options for how you power your home. There are wind turbines, an array of solar products and if you are blessed with a running creek or river on your property consider micro hydro. One room in the Earthship is used exclusively to house a panel, inverters and batteries to store your energy. Some folks still prefer to have a backup generator although as fossil fuels dwindle you may prefer to negate this option altogether. Finding ways to downsize your consumption can prove more valuable than trying to create more power. (Ex.) Use a clothes line instead of a dryer.
Earthships are completely self sufficient, and by that I mean they produce food, treat grey and black water on site, catch/store/filter rain water, create and store their own electricity on site, and heat and cool themselves for the most part passively due to their unique design. In short this home takes care of all your needs independent of the rest of the world except maybe companionship…you are still on your own for that. However, if you ask me, nothing is sexier than growing dwarf banana trees in your grey water planters indoors as it snows blustery cold outside.
Time to tally up the tab.
Advantages of an Earthship dwelling:
• Tire homes reduce our footprint by minimizing our pollution and dependence upon resources
• Recycling tires takes them out of the garbage piles where they can catch fire
• Recycling tires as a building material gives them a second life
• Recycled tires reduces the need to use wood products to build with thus saving forests
• Earthships use indigenous and local materials near the site (dirt, mud plaster, recycled tires, cans and bottles) reducing our demand for foreign or far away resources with high embodied energy
• A truly self sustainable home that can be modeled the world over
• You create your own electricity thereby in time saving money on hydro bills
• By harvesting rainwater and judiciously recycling it we protect ground and surface water from pollution and depletion
• This structure is resistant to fire, earthquakes, tornadoes, hurricanes, and vermin
• Blessedly quiet inside
• Dirt (to build with) can be found everywhere
• Reasonably easy to build as a DIY project given a workshop or two and some advice
• Non electrical homes can be built reasonably quickly in areas where disasters have occurred
• Can promote self sufficiently in developing countries
• In dry climates the humidity of the interior planters can be beneficial for breathing
• Earthships have a 30 year history have been accepted as a proven technology all over the world
• While the cost to build one is not less than conventional housing it isn’t more either, therefore its within reach to choose which one you prefer.
Disadvantages of an Earthship Dwelling:
• Permit approval varies from place to place.
• Thermal mass requires sun to work. If you get cloudy, dark days you will need backup heating such as a wood burning stove to warm the house.
• A lack of experience can lead to costly errors for the DIY
• Pounding tires is labour intensive and if you are hiring the labour that can be quite expensive
• Overheating can occur unless proper care is taken to vent airflow, to use curtains when needed, or plant deciduous plants that shade in summer, but drop their leaves in winter when heating is desired.
• If kitchens are located towards the front of the home directly in the path of the sun then the area may overheat making refrigerators work that much harder.
• Since sunlight floods the home it can cause eye straining glare on computer screens.
• Tire dwellings have less liveable floor space than a regular rectangular home due to it’s U shape, and space used for the planters, therefore if you want 1000 square feet of useable floor space you will need to build a larger earthship.
• U shaped walls don’t include closet and storage space unless you incorporate that into the design.
• Humidity is a concern due to the planters, and if you dry clothes inside it can be intolerable. Unless you live in a desert where the moisture is helpful you will need to separate the planters from the living space with a barrior.
• The open concept of the home facilitates air flow but doesn’t stop sounds from travelling from one room to the next reducing privacy.
• It can be a challenge choosing species that will thrive in an indoor planter.
• White flies and aphids may go after your plants inside just like they would with your garden outside.
• Cats think your planters are their personal kitty litter box which you may or may not agree with
You can check out Monica’s detailed photos of the Michael Reynolds’ Lone Butte British Columbia Build we attended for two weeks, on Michael Reynolds website.
Looking to immerse yourself in Earthship culture?
Check out the following books:
Earthship: How to Build Your Own, Vol. 1 by Michael Reynolds (Sept. 1990)
Earthship: Systems and Components vol. 2 by Michael E. Reynolds (Nov. 1991)
Earthship: Evolution Beyond Economics, Vol. 3 by Michael Reynolds (Sept. 1993)
Earthships: Building a Zero Carbon Future for Homes by Mark Hewitt/Kevin Telfer (2007)
Earthships 101, Part 1 of 10 http://www.youtube.com/watch?v=L9jdIm7grCY
Earthships New Solutions Movie Trailer http://www.youtube.com/watch?v=SEg74ZMP4tM
Earthship Documentary featuring The Potters http://www.youtube.com/watch?v=zP43_w8jO2I&feature=related
Garbage Warrior by Michael Reynolds: http://shop.mydownloadportal.com/shopv5/shop.asp?clid=3260&prid=5654