Green Building Blog

low cost eco-building

Cambridge University survey on eco-roofing November 30, 2015

Filed under: Building materials — naturalbuild @ 5:23 pm

Please consider completing this short survey about eco-roofing:

This survey is conducted by University of Cambridge students. The findings will help in the launching of a new, environmentally friendly roofing solution.

The survey will take you approximately three minutes to complete and your responses will help us better understand environmentally friendly housing options.


My house and home: Living in an eco-house August 23, 2013

We have lived in our new eco-house for six years now and at time progress has been very slow – we are only just feeling like we have got it how we want it to be. But it has also been far more transformative that I had imagined, knowing where my water and electricity comes from and where my waste goes has made me far more conscious about how I use resources. There is still something wonderful about having a sun-heated bath, and rejoicing when it rains because it fills the rainwater harvester. We had long held a dream to build somewhere that not only reduced our environmental impact and facilitated a more environmentally-friendly lifestyle, but would also dramatically reduce our running costs and increase our resilience to climatic uncertainty.

80    IMG_1349

Deciding to build an eco-house with my mother generated a surprisingly number of shocked responses from friends and family. They variously thought Maggie to be too old (she was only in her late 50’s) for such a challenge, and that she would cramp my life choices. Few understood how our skills, ideas and dreams complemented each other. Maggie had explored the idea of living in existing communities and we met with others interested in establishing new eco-co-housing schemes. But we realised we did not want to wait for the slowness of collaborative enterprises and that living together would provide enough challenges, and entail new ways of working together as it was.

DSC_0340    wood stove comp

We have taken a very pragmatic approach to the build. Inspired by the Centre for Alternative Technology and the Autonomous House we started with a utopian vision which was quickly scaled down. Our choices have been very much shaped by financial and practical limitations and a desire to complete the project so that we could get on with living the way we wanted to. We were determined to prove that older people and those with full-time jobs could still self-build and be eco. Although we had a sizeable budget it was also only slightly more than the average house price and we had no back-up plan.

DSC_0304   house 2

This budget bought us a small (10th of an acre) triangle plot in rural Leicesterhire, near Melton Mowbray. By facing south the house makes the most of passive solar heating through large A rated timber-framed windows, with thick dense block walls (made from 100% recycled aggregate) creating a high thermal mass (with sheepswool insulation in the roof) and reducing noise and vibrations from the abutting railway line. We wanted to build a house that was cheap to run and simple to maintain, only using technology we could understand and if necessary learn how to fix. The house remains at around 17 C without heating, even in winter, though we do have a Clearview wood stove as a back-up. Our solar thermal evacuated tube arrays also work all year round, and when the sun is not shining we heat water either by the wood stove or an efficient electric immersion. Our rainwater harvester feeds the toilets (low-flush IFO CERA from the Green Building Store) and washing machine, and we have low-flow showers to reduce water use. Energy use is much reduced by an induction cooker, A+ appliances, low-energy lighting and the bright aspect reduces the need for lights to be on. A couple of years ago we also installed photovoltaic panels and now (averaged over the whole year) we generate roughly the same electricity as we use.

DSC_0037  house 1

We tried, wherever possible, to source reclaimed, local, and untreated material. Our reclaimed pitch-pine floors came from an old Liverpool factory via the local salvage yard, our reclaimed-pine kitchen units and internals doors were made in Lincolnshire, our Douglas Fir deck has been left untreated, our jute and wool carpets were ordered from the local shop. We, of course, carried on using existing furniture, rescued some pieces from a tip, made some new pieces with help from my father, and added colour by painting tiles ourselves.

DSC_0359   DSC_0350

We developed some golden rules during the build: we would choose environmentally-friendly products over visual looks; we could not buy anything for the house without mutual agreement; we would worry more about cost than time taken to complete things; local suppliers and workforce were best; just because it was not the conventional way of doing things did not mean it would not work.

We struggled, at times, to communicate to others what we meant by eco: it took a while for my dad to understand reclaimed, native, or FSC wood and eco-varnish; the plumbers questioned what our washing would turn out like if we used rainwater; and the painters objected to using Osmo and ECOS paint. Early on we met plenty of patronising builders who advised us to ‘forget all that eco-stuff’ and raised eyebrows when they understood we were two women building a house. But with a highly supportive eco-architect (Andrew Yeats of EcoArc) and a knowledgeable project manager willing to engage with eco-ideas we eventually found suppliers and stockists of the things we needed. My partner, friends and family were invaluable in helping is complete the build – with seemingly endless shelving to put up, a woodshed to build, furniture to strip, and gardens paths to lay. Since moving in a local carpenter has agreed to drop off his off-cuts which we use to supplement our homemade newspaper logs and purchased logs for the wood stove, and a neighbour has offered us free seedlings for our garden. Our house has started all sorts of conversations and we have often invited in passers by who have stopped to ask us questions.

 House Nov 08    DSC_0362 

At times we have to remind ourselves why we made certain compromises (often due to a lack of money or plot space). Now the project is complete we have the confidence in our choices to wonder if we couldn’t have been bolder in some of our earlier decisions. Externally the house has a big visual impact on the landscape (ironically a result of the planning permission which stipulated that it replicate the look of the previous house demolished by Network Rail). We have tried to mitigate this impact by covering the lower external walls with red cedar cladding and choosing a dark slate-effect roof (using Ardesia recycled tyre roofing), but we could have been more radical in our design. We now have the confidence to follow our gut instincts and compromise less in our search for environmental solutions. We only hope that our house will inspire others to follow their dreams too.


A verion of this article first appeared in Permaculture Magazine


Evaluating the success of an eco-house March 4, 2013

Filed under: Building materials,Notes from fieldwork,Photographs — naturalbuild @ 9:43 am

How do we judge how ‘good’ an eco-house is? By its ecological performance, what it feels like to live in it, how long it lasts, how much it cost? All of these are used, some formally in post occupancy evaluation, and others more informally in judging what worked and what hasn’t in new buildings. Post occupancy evaluation seeks the opinion of those who live (or work) in buildings, but too often eco-houses are judged just by their cost versus carbon emission savings, or how robust they are. While I am most interested in the balance between building a structure which is ecological as well as nice to live in, and thus tend to focus on people’s experiences and feelings about their homes, I know that we also need to measure the performance of buildings, especially in how they keep warmth in or not.

Recently I have been using a thermal imager, newly purchased by the Geography Department at the University of Leicester, to explore how much houses lose their heat.

IR000029  IR000076

Thermal image (at night) of a conventional house (to the left) and a straw bale eco-house (to the right)

Comparing a straw bale house (in North Yorkshire) with a more conventional house in similar freezing temperatures it was clear to see the benefits of eco-building in terms of reducing heat loss. The conventional house leaked heat – with its external wall temperature as high as 15.9C, whereas the straw bale house external wall temperature was only -2C. Both houses where heated internally and where between 18 and 20 C inside. Notably the ‘hot spots’ on the image for the conventional house where were the radiators were on the wall – the heat was literally leaking straight out of the walls and windows next to the radiators.

Of course, a thermal image only tells us so much. It cannot judge for us which is the most comfortable house to live in. We can assume that the conventional house leaking heat probably costs more in energy consumption, that it is less ecological, and that the internal temperature is more uneven. Likewise we can assume that the straw bale house has low energy costs, has an even temperature and is more ecological. But what does it feel like to live in? Does it feel warm and cosy? Which would people prefer to live in? All these are qualitative questions about feelings, emotions and expectations and cannot be measured by scientific results alone. We need to continue to develop creative ways in which to judge the success of eco-housing and not rely on measures of energy efficiency alone.

[Jenny Pickerill, March 2013]


Earthship Biotecture, near Taos, New Mexico, USA May 17, 2012

Standing on top of an Earthship in the New Mexico desert watching the sunset turn the mountains a deep red, makes you realise how boring conventional housing is. Earthships are a highly inventive and unusual house design by Mike Reynolds who spent years experimenting in the New Mexico deserts. There are now hundreds of examples worldwide but I wanted to come to the place of their inception to try and understand their possibilities and questions around affordability.

Sunset view from top of an earthship at the Greater World Earthship Community in New Mexico, USA

An Earthship is an autonomous building made from car tyres filled with waste (such as drinks cans and bottles) to produce highly insulating walls. The Earthship has been replicated in the UK (Fife and Brighton), Holland, France, South Africa and India. There are now 3,000 Earthships globally. The design, often built into the ground, not only uses recycled and natural materials, but by using passive solar heating (and cooling), water harvesting, contained sewage treatment, and internal food production (through conservatories), creates a self-sustaining building with a stable ambient temperature even in climatic extremes. Built to be cheap, efficient and autonomous, Earthships represent radical ecological architecture designed to reshape our relation to the environment and our daily lifestyles.

“The Earthship concept is meant to place shelter and a less stressful method of living within the immediate grasp of people. If land is made available for no profit; if shelter can be obtained with little or no mortgage payment; if utilities come free from the sky; if much of our food can be grown in our homes; people will become more mobile with their thinking. They will begin to have time to think of each other and the planet” (Reynolds, 1990, p.254)


An Earthship at the Greater World Earthship Community in New Mexico, USA

There is a great sense of freedom from knowing that a house has everything you need to survive without needing to be connected to anything else. All the systems are holistic and autonomous. Standing on the roof I am next to the water cistern which collects the rainwater, and overlooking the PV panels and solar thermal hot water heater. Moreover all resources are used as efficiently as possible, for example, rainwater is used three times – for drinking, to flush the toilet and then to water plants. Having stayed in one at the height of summer I can also confidently confirm that it works – nice and cool during the day, warm at night and not too dark inside. Such autonomy also enables the resident to more clearly understand how houses work – if you are not careful you will use up all your water – and thus, potentially, how to look after and fix it.

Inside the studio earthship at the Greater World Earthship Community in New Mexico, USA

By watching the sunset you also realise that Earthships enable a landscape without wires. Look out of your door – do you see wires? Most houses are linked by electricity and telephone cables criss-crossing the landscape, but here there is only sky: huge big open skies. It is a liberating view compared to most outlooks from houses. In New Mexico all you can really see of the houses are the windows reflecting the sunlight. It is a very calming view.

Phoenix Earthship at the Greater World Earthship Community in New Mexico, USA

Earthships are more than simply highly integrated autonomous houses, they are amongst the most radical and inventive green buildings I have seen. So inventive that new systems, such as water and power management systems, have been designed specifically for them. But they do have an unusual aesthetic, they do not look anything like a house as conventionally understood – buried in the ground, glass wall to the south, curved walls inside, and glass bottle walls. This of course potentially limits wider adoption. Personally I find them rather beautiful buildings to look at, but then I already love eco-houses and all things quirky. Replication is not only limited by how they look however, but also by their requirement for manual management (such as opening vents and closing blinds) which in an age of ‘on demand’ heating and air conditioning puts some people off.

The houses were designed to be highly replicable, and Reynolds has gone to great effort to build demonstration houses around the world and to create plans and ‘off-the-peg’ designs which can be purchased and followed. The use of the metaphor of the ‘ship’ in its name also signifies that such designs should be replicated elsewhere (that the ideas should travel, they were designed to run without fuel, use rubbish and thus locate anywhere); that these ships should be part of a broader network (that we should exchange and develop these ideas); that ideas need freedom to enable experimentation and radical innovation (the ship as autonomous and free from regulations); and, finally, that they will “sail on the seas of tomorrow” (Reynolds, quoted in Paschich and Hendricks, 1995, 73) (and thus continue to travel into the future).

Yet this replication has not happened in the way that might have been imagined. The design is robust, tested and cheap and yet few Earthships exist. In addition to how they look and what it is like to live in them, they are not the easiest to build – they require time and effort (and strength and perseverance) in a way that brick houses do not. Finally, they are not appropriate for all places, they have been developed to work best in the climate of New Mexico and as the Brighton Earthship has shown, if changes are not made to the design when built in other climates then they do not work as well (in Brighton the floor is rather cold). This could be overcome, but only with further experimentation and the freedom to adapt Reynolds designs.


Inside the studio earthship at the Greater World Earthship Community in New Mexico, USA

Earthships can be built expensively or cheaply, it all depends on choices made by the builder. They are designed to be extremely low-cost to run, but to make the actual build cost lower then there is a need for self-build (using your own labour, also called ‘sweaty equity’), build on cheap land (hence the growth of such houses in the deserts of New Mexico), use waste materials (there are some plans for Earthships using concrete), ignore building codes, and keep the design simple and small scale (thus ‘designing down’ the house so that you need less electricity in everyday running). Reynolds argues that “just as the sun allows no darkness, the lake allows no dryness, the wind allows no calm, the river no silence … the Earthship allows no poverty” (1993). However, some have complained at the high cost of the step-by-step designs to build an Earthship.

An Earthship at the Greater World Earthship Community in New Mexico, USA

There are many lessons to be learnt from Earthships which could be, and should be, applied to eco-housing elsewhere. It is a bold design that works: the result of years of practical experimentation and radical innovation. Whether it is about their autonomy, low cost, low visual impact, self-build nature, or the way in which every resource is carefully harvested and used multiple times, we need to understand and learn from Earthships. The strongest memory for me is of sitting on the roof watching the sunset knowing that I would be warm and cosy that night, that there was amble water and heat for a shower, and that the environmental cost of all that comfort was minimal. It was a guilt free sunset.

There is a Visitors Centre at the Earthships near Taos (#2 Earthship Way Taos NM 87571) which is open 10am to 4 pm, 7 days a week.


Key references about Earthships:

Freney, M (2009) Earthships: Sustainable housing alternative. International Journal of Sustainable Design, 1, 2, 223-240.

Harkness, R (2011) Earthships: The homes that trash built. Anthropology Now, 3, 1, 54-66

Hewitt, M and Telfer, K (2007) Earthships: Building a zero carbon future for homes. HIS BRE Press, Watford

Hodge, O (2008) Garbage Warrior (Film). A Co Production of Open Eye Media UK, ITVS International & Sundance Channel.

Ip, K and Miller, A (2009) Thermal behaviour of an earth-sheltered autonomous building – The Brighton Earthship. Renewable Energy, 34, 9, 2037-2034

Kemp, S and Cowie, P (2004) The Earthship Toolkit: Your Guide to Building a Zero Waste, Zero Energy Future. Sustainable Communities Initiatives, Kinghorn.

Paschich, E and Hendricks, P (1995) The Tire House Book. Sunstone Press, New Mexico.

Reynolds, M (2000) Comfort in any climate. Solar Survival Architecture, Taos, NM.

Reynolds, M (2005) Water from the sky. Solar Survival Print, Taos, NM.

Reynolds, M. (1990) Earthship Volume I. One Solar Survival Press, Taos, NM

Reynolds, M. (1993) Earthship Volume III. One Solar Survival Press, Taos, NM


Learning from Lilac: Low Impact Affordable living in Leeds, Britain March 5, 2012

Filed under: Britain,Building materials,Cost of housing,Inspiring examples — naturalbuild @ 8:22 pm

Apologies to those not in Britain, but there is a really interesting workshop coming up on 10th May in Leeds. Lilac stands for Low Impact Living Affordable Community. It is a member-led co-operative housing society building an affordable, cohousing community in Leeds. They are using a co-housing design approach to build 20 houses and a common house from strawbale and timber through a prefabricated product called Modcell (enabling cheap, quick, collective and local construction).

They have just started building (on a 0.7 hectare site in inner city Leeds) and there is a lot to be learnt from this project. In particular they have deliberately organised the project to remain affordable in perpetuity using a mutual home ownership model. In effect each resident pays just 35% of their net household income towards the costs of living at Lilac (and thus if you earn more you pay more). This is not just paid as rent however, all residents co-own the project (through equity shares) and as such all have a vested interest to make it work and maintain it. In order to ensure that the project was within their available budget they have had to make compromises, such as using gas as an energy source, and only aiming to achieve Level 4 of the UK Government’s Code for Sustainable Homes. This was done in part, however, to balance the energy needs of occupants with the cost limitations and is indicative of a participatory and considered approach to low impact and lost cost building.

Lilac also received a £420,000 grant from the Homes and Communities Agency (UK Government) and have funded the bulk of their initial costs through a loan from the bank Triodos.

The group have spent several years reaching this point and have spent considerable time ensuring that the process of the project was democratic and inclusive. They have developed several ‘community agreements’ which all residents have to agree to abide by and include forgoing have tumble dryers and dishwashers in their personal units, using the communal washing machines, and outlines how the communal spaces will be managed. They are also restricting the number of cars on site, insisting on car pooling and have tried to ‘design out’ carbon intensive activities. Overall, this is an exciting project and definitely one to follow. I am not personally involved, however, several of my long time friends are central to the project so I might be a little biased!

++++ Learning from Lilac: An invitation to a day workshop ++++

In association with the UK Cohousing Network (

Thursday 10th May 2012. 10am – 5pm
School of Geography, University of Leeds. University Road. Leeds. LS2 9JT.

Lilac is hosting a day to share its learning to help other similar projects develop their ideas into reality. This day is aimed at those who wish to set up housing projects who have an emphasis on being – community-focused, low impact, co-operative, affordable, member-led, mutual. Topics in the morning will briefly cover:

.       The Lilac project in brief so far – key milestones, challenges, successes
.       How to go about finding land
.       Options for financing your project
.       Developing good group process and making decisions collectively
.       Attracting members
.       The Project Manager and what they will do for you
.       The Quantity Surveyor and what they will do for you
.       The Solicitor and dealing with legal issues
.       Ways forward, networking and supporting projects

Additional topics will be covered in the afternoon reflecting the interests of participants. Please use the form below to state the topics you would like to see covered (for example Lilac’s Mutual Home Ownership model, Lilac’s environmental strategy, grant finding, what is cohousing, the role of a common house).

+++ To Book your place +++

Places are limited to 30 participants. To book your place please send a cheque for £10 payable to ‘The University of Leeds’ and the booking form to: Paul Chatterton, School of Geography, University of Leeds, University Road, Leeds, LS2 9JT.

For further information about the day contact:

[Leicester, 5th March 2012]


Earth Building UK Conference 2012 December 21, 2011

Filed under: Britain,Building materials — naturalbuild @ 4:34 pm

For those of you in the UK there is a really interesting conference in a few weeks time in York. The organisation Earth Build UK  is having a conference on ‘The use of earth and clay plasters’. The organisation aims to promote and support building with earth in the UK by:

  • promote earth building in contemporary construction
  • assist the recognition, understanding and significance of earth buildings
  • foster traditional skills and promote new technologies
  • network our membership to promote earth building locally, nationally and internationally
  • research and develop technical understanding
  • share experience and knowledge through a program of seminars and annual conferences.

The conference is on 13th January and includes talks by Tom Morton (Arc Architects, Annabel Fawcus (EarthedWorld, Ben Gourley (University of York), Nigel Copsey (Earth, Stone and Lime company, Andrew Heath (BRE Centre for Innovative Construction Materials, University of Bath, Adam Weismann and Katy Bryce (Clayworks, Barbara Jones (Straw Works and Neil May (Natural Building Technologies

The conference fee for EBUK members is £42.00. This includes refreshments and lunch. If you are not already an EBUK member the conference fee is £63.00 (this includes a full year’s membership of EBUK).


Ampersand Learning Center, Cerillos, New Mexico, USA March 8, 2011

“In a quality life, the sense of fulfilment comes from connection. Look to your rain, look to your land, look to the magical seasons of this earth. Listen to the wind, dance in the mud, then plaster your house with it … living intimately and comfortably with the basic elements brings a deep sense of fulfilment” (Amanda and Andy Bramble, 2010, p.154)


Ampersand Sustainable Learning Center is an intriguing mixture of teaching space, collective building, embryonic community, and a remote eco-home. Situated south of the small town of Cerrillos in New Mexico, Ampersand is at the end of several tracks snaking into the hills. In construction since 2003, the buildings here are mostly hybrid, a mixture of straw-bale walls, adobe and earth bags. Many things have been fashioned from reclaimed items such as salvaged windows, reusing wood, or using an old swivel office chair as a base for a solar oven (thus being able to move it to best catch the sun).


The main house

There is a main house – the home of Andy and Amanda Bramble – and then other more collective spaces such as a straw bale guest house, an outdoor kitchen for guests and another guest building to which a new bathroom was being added. There is also an outdoor solar shower. All the spaces are compact – making use of sleeping platforms, open plan design, and careful placement of furniture – and there is a beautiful simplicity to many of the rooms. There is enough for comfort but not clutter and certainly not an excess of things.


The straw bale and a plaster wall design

This simplicity is also evident in the way everything is designed to be efficient and minimise waste. For example, the solar thermal hot water panel is just outside the bathroom meaning it does not have to travel far to the point of use, and they feed used water into the indoor planter to water the growing vegetables – making multiple uses of what they have.


The outdoor shower

Ampersand is completely off-grid – generating all their electricity from photovoltaic panels, using solar thermal to heat water, collecting all their water via rainwater (into a 2,500 gallon tank) and using a solar oven for cooking. They also warm and cool their house passively. The back of the main house is built into the ground with only a couple of very small windows looking north from the pantry. To the front they have a greenhouse, as this heats up they let heat in through internal windows and when it is cold outside the greenhouse acts as a barrier while still letting the sun in. Their water use also is extremely low, about six gallons each per day. Water is then filtered through a Big Berkley system ready for drinking.

Growing food out here is difficult so they have built a large greenhouse to the front of their house with an indoor planter and created a large storage space – a pantry built into the ground at the back of the house. Refrigeration is limited, they “we harvest ice from an open-topped cistern in the winter to keep our food cold” (p.154) but have to use a propane powered fridge at times in the summer.

Ampersand aims to demonstrate “low-tech sustainable systems which people can do themselves, so that they are not reliant on experts” (Amanda Bramble). There is an emphasis here on having the skills and courage to do it yourself and key to this is starting small and simply learning through the experience of building small structures. It is also about building as a collective endeavour.


Inside and outside a straw bale house at Ampersand Learning Center

I can’t help but fall in love with the simplicity of some of the design and materials used here. In the straw bale guest house there is everything you need and no more or less. Everything is low cost, reclaimed, salvaged, adapted and yet it all has a beauty too. When I asked Amanda what barriers might exist in getting mainstream society to understand and value a place as eclectic as Ampersand she argued that the main obstacles are the “mental constructs of what is acceptable beauty and lifestyle”. Of course it can so easily come down to one’s own choice of aesthetics, but to me this is a place made for the future.


Off-road track to Ampersand Learning Center  and the straw bale house

If you are interested in visiting Ampersand they run classes in the spring and summer, volunteer days, have open house visit days, and occasional internships. Details are on their website:

There is also an article written by Amanda and Andy in Sustainable Sante Fe (2010) ‘On being a beneficial influence: Off grid at Ampersand’