Updated: Mar 25
In the wake of COP26 and increasing government guidance reducing the carbon impact of construction, sustainable construction has become a buzzword within the industry. But do we need to consider more extreme methods if they deliver carbon-neutral living?
I was recently made aware of sustainable construction methods that created homes named Earthships.
Honestly, at first, the name put me off slightly, I wondered if it would somehow related to alien conspiracy theories.
After some intense research, however, I was enchanted. These homes seemed to address some of the major worries surrounding sustainability, recycling, and waste, as well as concerns surrounding the lack of homes, how homes can be made sustainable for the future, or what living in a sustainable way, might look like in 10, or 20, or even 50 years’ time.
Maybe homes built with rubbish are the answer to creating a truly sustainable construction industry?
What is an Earthship?
The creator of the Earthship is Michael Reynolds, who started to build homes in the 1970s that directly questioned traditional architectural ideals. Fed up with “…pretty, but pretty useless boxes…” Reynolds instead designed ‘passive solar homes made out of natural and recycled materials,’ allowing inhabitants to live truly off-grid, truly sustainable lives.
Earthships are built from 40% natural or recycled materials, utilising waste materials, such as car tyres, aluminium cans, plastic drinks bottles, and glass bottles, that are used in the construction of the foundations and walls of the home. They are completely self-sufficient, featuring in-built solar and wind power sources, and provide clean drinking water, from rainwater collection that is then cleaned and reutilised with in-house waste water management systems.
Architecture develops pretty, but pretty useless boxes. When you buy a house, you have to plug it into the water, into the energy, and into the sewage system or your house is useless. These are the kind of houses we still looking at in the future.
Earthships are built predominantly by hand and start with stacked, earth-packed tyres that provide the stability needed for the loadbearing walls of the building. Next, a thermal wrap is applied to regulate the temperature of the building, and non-loadbearing walls and recesses are honeycombed with concrete and other waste recyclables such as glass bottles, plastic bottles, and aluminium cans.
These are then usually plastered with stucco, ‘a cement-type mixture made of Portland cement, lime, sand and water. It is a thin finish coat that goes on the outermost layer of residential and commercial constructions.’ This plastering can cover most of the unconventional building methods, and if preferred, can create a finish that looks very ordinary, as you can see in image 1. However, if the homeowner is willing to create something more out of the ordinary, building materials can be arranged in a way to increase the aesthetics of the building, and create patterns in walls, or beautiful stained-glass effects. (As you can see below.)
Earthship rooves are heavily insulated and are designed to include cisterns and aqueducts to collect and move rainwater to internal water collection points and are also covered with earth or adobe, ‘an ancient building material usually made with tightly compacted sand, clay, and straw or grass mixed with moisture.’
Floor to ceiling windows are utilised in Earthships to warm the homes, heat water, and grow food, and other plants in indoor botanical cells. These large windows let in vast amounts of light and heat and often buildings are built-in horseshoe shapes to ‘maximize natural light and solar-gain during winter months.’ Skylights are also often utilised on the buildings to allow for ventilation.
Why might people want to build their own Earthship?
Earthships main USPs are quite convincing and appear to provide the perfect solution to modern housing, energy, and food production problems.
They proudly proclaim of total yearly utility bills of a mere $100(around £73.33), and reportedly only use around 1/6 of the power of a standard home. So anyone currently experiencing increasing energy bills may be tempted indeed by the Earthship.
Due to their built-in wind and solar energy harvesting features, such as wind turbines and photovoltaic panels, the energy needed to run electrical items within the homes, such as televisions, tablets, or even your PlayStation, is generated and collected by the structure of the house, and is stored in deep-cycle batteries, normally within the roof. This generated DC energy is put through a Power organising Module, which converts it to AC energy, enabling you to run electrical devices. For free.
Earthship owners can also rely on fresh, clean water to drink, and mod-cons such as showers and flushable toilets, thanks to the Earthships water harvesting and contained on-site sewage treatment. This process is an extension of the usual water system, with the inclusion of contained sewage treatment planters, also named ‘botanical cells,’ used to clean and filtrate used water, to allow it to be used up to 4 times. The use of roof cisterns and gravity-fed Water Organisation Modules filter out bacteria and contaminants making water clean enough to be drunk, or for general use in the household, so for example for cleaning- though usually without harsh cleaning chemicals.
Water that has been used once and is no longer clean enough for drinking is called ‘greywater,’ and once it has been recollected, is passed through a grease/ particle filter, and into 30-60-inch-deep, rubber-lined botanical cells, in which food-producing plants are grown.
‘Oxygenation, filtration, transpiration, and bacteria-encounter all take place within the cell and help to cleanse the water. Within the botanical cell, filtration is achieved by passing the water through a mixture of gravel and plant roots. Because of the nature of plants, oxygen is added to the water as it filters, while nitrogen is removed. Water taken up through the plants and transpired at their tops helps to humidify the air. In the cell, bacteria will naturally grow and help to cleanse the water.’
The greywater that has been through the botanical cell is then filtered again and goes on to be used to flush toilets. Once this water has been used within the toilet, it is known as ’blackwater,’ and this is sent to an on-site solar-enhanced septic tank, to help break down waste, before it is pumped into outdoor planter cells, where more plants can be grown. This enables the waste to be disposed of safely, used as fertiliser, and creates pleasant window-box style planters for the property.
The water system utilised within Earthships successfully provides all the amenities homeowners would expect from a traditional home, clean drinking water, washing facilities, the ability to run a washing machine, and safe blackwater removal, with the ability to grow well-nourished gardens, that attract and support local ecosystems.
We could also wave goodbye to increasing food prices, by growing our own in our Earthships. These homes feature indoor botanical cells where inhabitants can grow 25-50% of their own food, with the potential for more if they have a plant-based diet, using the harvested rainwater and sunlight that streams into the home from floor-to-ceiling windows. In his TED Talk, Reynolds' even explained that homeowners could fill their botanical cells with fish, ready to be caught fresh before the evening meal!
Living in a fully Carbon-Zero home also provides homeowners with the chance to do what they can to escape the anxiety of climate change and take a clean break from a world that increasingly seems at odds with nature. By living more simply in an Earthship, residents can remove most of their ecological footprint, and therefore the damage humans are currently inflicting by living as we are accustomed to.
Why can Earthships be expensive?
Earthships are not always cheap, and range in price from ‘$20,000 to $1,500,000 (equivalent to £14,615.89- £109,611.66) depending on factors such as:
climate and local environment,’ and
the design and size of your Earthship.
However, as of October 2021, the average UK house price was an eye-watering £268,349 a precedent set to continue in 2022, as prices continue to increase, leaving people wondering if using Earthship Biotecture to build their own is worth a second look.
Labour, Materials, and Design Costs
As with any custom, handmade project, labour costs are goingto be significantly increased, as the project is likely to require a large team of skilled labourers, and a longer preparation and build time.
Material costs are also something to consider in your Earthship. Although around 40% of the construction materials can come from natural or recycled materials, these may not always be free when sourcing them in the number required to build with, as the average Earthships will require around 1,000 car tyres.
The remaining 60% of required materials will include expensive items such as floor-to-ceiling windows, concrete, and building materials designed to keep out the damp and maintain the internal temperatures of the house, for example, Foamglas, which was utilised by successful UK Earthship builders Daren Howarth and Adi Nortje in 2009.
Similarly, as the footprint of your home increases, so will the price of construction, as labour and material costs will also continue to escalate.
Climate and Local Environment
Earthships in the US have been constructed in areas such as Taos, New Mexico, where the climate is warm enough in the day to be comfortable, and in the cooler temperatures of the night utilises ‘a combination of sun exposure and passive heat storage,’ to keep them a comfortable temperature for human inhabitation.
In England, we often joke about our poor weather, so is it warm enough to support an inhabitable Earthship?
In northern climates, the sun is only able to provide heat during a shorter part of the day during the winter. It takes a lot of time to heat up the Earthship, and the interior temperature will drop more quickly at night.
With the inclusion of built-in insulation materials, such as Foamglas and insulated glazing, to maintain internal temperatures, and backup heating sources such as wood, or pellet stoves, some agree that Earthship homes could be warm enough in our country to support full-time habitation. However, with both Earthships in the UK not currently being used for residential purposes, we are unlikely to know with any certainty until the first UK Earthship home is built and tested.
The technology for carbon-zero living is here but codes and regulations are slowing it down.
As these buildings are non-industry standard, in many locations across the world getting the required permissions and permits can be tricky, or nigh-on impossible. Reynolds' himself has remarked about how Earthships builders from the US often contact him for advice with permitting issues, and his main advice is ‘move.’ As state laws differ largely across America, so do building regulations, and often to embark on their dream of building and living off-grid, homeowners move to areas with little-to-no permitting requirements.
In England, Earthships have been built successfully, in Fife, Scotland, and Brighton, but required advice and support to receive planning permissions, and were not built as residential properties. Problems may arise from many areas when seeking the appropriate permissions, as, without it, structures can be forcibly demolished and removed. It is always best to go for advice from your local planning department and a solicitor with building experience before embarking on your journey.
So, are Earthships the answer?
Unfortunately, this may not result in a simple yes or no answer.
Firstly, the Earthship project first began in New Mexico and continues now across the globe in countries such as Australia, the Galapagos Islands, and Brittany, France- all of which have a warmer climate than we experience here in the UK. Although an Airbnb-style, rental Earthship has been built in Montana, and non-residential Earthships have been built in the UK, it is yet to be determined if our climate could support year-round residency within an Earthship. If it can be supported, it will likely result in the inclusion of wood, or pellet, burning stoves to add to the thermal storage of the tyre walls, due to the limited light levels we experience in the autumn and winter months.
Secondly, due to this rarity, seeking planning permission, and finding construction teams with the appropriate training to assist you with building your Earthship may remain tricky, and costly for the foreseeable future.
Further issues with Earthships relate closely to those faced by the construction industry, namely, the increasing cost of building materials such as concrete. Over 2021, concrete experienced an ‘unprecedented 30% [rise]over the year,’ a charge that Earthship homebuilders will be unable to avoid. Similarly, they will also be able to avoid the environmental impact of using concrete to construct internal walls, as it remains the ‘third highest global emitter, annually accounting for 8% of total CO2 emissions.’
However, by living according to the principles of the Earthship, by producing and using your own electricity, water, and food, reusing water, and utilising naturally occurring thermal solar heating and cooling, homeowners could have a vast impact on the amount of CO2 they produce. By simply changing the way they heat their homes, Earthship homeowners can save on average of ‘2.7 tonnes of CO2 every year.’ Likewise, energy emissions could drop by ‘around 3.2 tonnes per year,’ per household in the UK.
To conclude, although they are not yet a proven option for year around habitation, and they do still feed into the carbon production of construction materials such as cement, Earthship living can drastically reduce CO2 production in many areas and can mean that many can reach carbon zero living, while still living with the amenities and comforts now seen as essential.
They may not be for all, but for those looking for a solution to the environmental and economic crises, Earthships may well hold the answer.
 National Geographic, film called ‘Earthships: A House Made From Beer Cans Sparks a Movement | Short Film Showcase,’ directed by Flora Lichtman and Katherine Wells <https://www.youtube.com/watch?v=Gfw5kwPzhP0>
 Forbes.com, ‘What Is Stucco Siding?’ <https://www.forbes.com/advisor/home-improvement/what-is-stucco-siding/>12.01.2022
 Thoughtco.com,‘All about Adobe- Sustainable and Energy Efficient,’ by Jackie Craven,published 16th August 2019, ttps://www.thoughtco.com/what-is-adobe-sustainable-energy-efficient-177943>
 Environment-ecology.com,‘What is an Earthship?’ <http://environment-ecology.com/environment-and-architecture/375-what-is-earthship.html> 12.01.2022
 Quote from Michael Reynolds, from his TED Talk ‘The Art of Carbon Zero Living,’ 11.22.2009,
 Environment-ecology.com,‘What is an Earthship?’ <http://environment-ecology.com/environment-and-architecture/375-what-is-earthship.html> 12.01.2022
 FreedomResidence.com,‘How much do Earthships actually cost to build?’ <https://freedomresidence.com/how-much-do-earthships-actually-cost-to-build/> 12.01.2022
 FreedomResidence.com, ‘Can you build an Earthships anywhere?’ <https://freedomresidence.com/can-you-build-earthships anywhere/#Local_Climate_Considerations>14.01.2022
 FreedomResidence.com,‘Can you build an Earthships anywhere?’ <https://freedomresidence.com/can-you-build-earthships-anywhere/#Local_Climate_Considerations>14.01.2022
 Quotefrom Michael Reynolds, from his TED Talk ‘The Art of Carbon Zero Living,’11.22.2009, ttps://www.youtube.com/watch?v=FON-UK_1kyI>
 ConstructionEnquirer.com,‘Industry to be hit with 16% cement price hike,’ <https://www.constructionenquirer.com/2021/11/01/industry-to-be-hit-with-16-cement-price-hike/>14.01.2022
 ConstructionNews.co.uk,‘Cement: how its carbon impact can be reduced,’ published 22.10.2021 by TimClark, ttps://www.constructionnews.co.uk/sustainability/carbon-cementing-net-zero-22-11-2021/eea=aitEbjlmN3ZGQTcxbjlzQzdObTlNQ2NRTG9XWmRzOTR6Smhuamx4VXY5VT0%3D#038;utm_source=acs&utm_medium=email&utm_campaign=CONE_CN_MAR_WYMHM-211126%20-%20A/B%20test%20on%20subject&deliveryName=DM17572>
 Citu.co.uk,‘What is the carbon footprint of a house?’ <https://citu.co.uk/citu-live/what-is-the-carbon-footprint-of-a-house>14.01.2022
All images, including cover image, from Earthshipglobal.com, <https://www.earthshipglobal.com/design-principles>15.01.2022