Two Hybrid Timber-Bale-Cob Houses in Cantabria, Northern Spain
You may remember I visited a rather spectacular natural building complex in Cantabria a couple of years ago. You may remember two straw bale houses in the process of being built. Those houses are now complete (yippee!) Robert Alcock from Abrazo House gives a brilliantly detailed rundown on how they were made, and shows us around.
If you're a regular follower of the Mud Home blog you'll have already read a bit about Abrazo House. At this ecological learning centre in a tiny village in the green mountains of Cantabria, we've spent the past fourteen years building natural homes and doing permaculture with the help of hundreds of volunteers from all over the world. You can read all about the project in our free ebook: (http://abrazohouse.org/en/book/)
In 2016 we decided to apply our hard-won experience to a further natural building project: to create two new, beautiful and efficient eco-houses on another plot of land in the same village, with the aim of attracting like-minded people to live and work in this amazing part of the world. The houses are now complete and are on the market. (http://abrazohouse.org/for-sale/) For all you natural building fans out there, here's a quick rundown on the essentials of the project.
The site is 5000m2 of south-facing terraces with young woodland (planted after we bought the land in 2005) and a stream, in a small village in Cantabria. The "urban" zoning of the land meant we could get permission to build two homes there, and we went down the legal route of architect's plans and municipal permits. (NB We've never run into legal issues because of the unconventional nature of our buildings.)
Because of the steep, south-facing site, we decided to cut away into the hillside and build earth-sheltered houses. A key design element is the addition of a semi-enclosed garage to the north, in between the house proper and the hillside: basically doubling your useful space for just the cost of the roof.
The choice of materials was based on ten years' experience of natural building in this bioregion. Of course there would be loooads of cob: we love working with cob, it's cheap and easy to mix with our well-honed rotavator technique, and it makes gorgeous organic shapes. But we wanted these houses to be completely passive solar—not needing any additional heating in winter—and cob alone isn't quite warm enough to do that even in our mild climate, so we went for a hybrid construction: straw bales laid on edge (35cm thick) with a good 15cm of cob inside and out for protection and thermal mass.
A notable feature of our local landscape is the humungous areas of eucalyptus plantations. These non-native trees are mostly used for making paper, but they actually make a very good structural timber which is very durable if treated with borax solution. So we decided to erect a timber frame structure and green roof first, and build the bale-cob walls afterwards, allowing us to work under cover. We cut and peeled our eucalyptus trunks on a friend's land, less than 1km from the building site. Using them in the round meant stronger beams, and saved us an expensive trip to the sawmill.
Earthmoving and Foundations
On site, our digger crew scraped away the topsoil—which we piled up for use in mixing the cob later on—and found that the underlying subsoil wasn't soil at all, but rock. This meant a lot more expensive digging, but it did have two benefits: a nearly infinite supply of stone for building retaining walls and foundations, and a very solid base for the houses, with no need to pour a concrete foundation. In some areas we could go straight up from the bedrock; in other places we built a brick pier for the posts to rest on.
Timber Frame and Roof
Due to administrative delays we weren't able to start building the timber frame until December 2016, but once we got going it went up in just a couple of weeks. With the main frames up and temporary supports in place, we put on the rafters and the roof during the winter, luckily blessed with good weather, and were ready to start filling in the walls by March.
To keep the bale-cob walls dry, you need a good stemwall. Despite having plenty of stone on site, our stemwalls are mostly built from termoarcilla, a specially insulating type of brick that interlocks like Lego, because it's way quicker: we only used stone on the visible exterior walls. We filled in between the two layers with expanded clay pellets (arlita) — a lightweight insulating pellet that's a bit like Rice Crispies.
On top of the stemwall we put a thin layer of cob, and then it was bale time. It was pretty easy to keep the bales straight and stable by tying them to the post-and-beam structure; in some places, we strengthen them with bamboo poles tied through the wall from inside to outside. At this stage we just left a big enough gap for each window or door, added a wooden lintel and kept going with the straw bales. It's important to take into account that the straw bales will settle over time, so the lintels must be able to move with them. (Our lintels could have done with being a bit stronger, too.) Later on, we would come back and hang the doors and windows from the lintels, filling in around them with slip-straw.
The first layer of plaster we added to the bales was a clay slip—just clay soil and water mixed by hand and foot in a pit (an excellent way to make friends and get incredibly muddy), and applied to the bales by hand.
Electricity tubes get fixed straight on to the straw bales. Then it's time for the cob plaster—layers and layers of cob plaster until the walls are weatherproof, thick and straight.
On top of the cob we applied Ecoclay, a commercial earth plaster—basically a much finer version of cob. Then came the finish layer: gypsum plaster inside the West house and an extra fine commercial clay plaster in the East house, with lime plaster on the exterior of both houses for strength and durability.
On the market
The two houses are now on the market, together with 5000m2 of land with wooded terraces and a stream. The East house is furnished as a small family home, while the West house is slightly larger, with a loft and two bathrooms, and would be ideal as a studio space for working, running courses or as a rental property. We believe this is an exceptional property for the right people, who are looking for a place to realise their dreams of a life in harmony with nature. Please take a look at our webpage (http://abrazohouse.org/for-sale/) or check out our promo video (https://youtu.be/mgMiTj5ujCA) and get in touch if you want to know more.
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It was an amazing mud adventure. Kim Siu’s gorgeous hobbit house in Moray is now finished, and it's a showcase of natural building. It ticks every box: a straw bale house with rubble trench foundations, living roof, earthen plaster, wattle and daub/cordwood interior, and a stunning earthen floor. Not only that, but it was built to code. In the UK. Yup, you read that correctly. It’s 100% legit. Building permits In. The. Bag.
But let’s not lie. Clawing your way over those bureaucratic hurdles is anything but a picnic. “I’m not building again,” says a somewhat frazzled Kim this end of the build. “I don’t think my frayed nerves could take it. Two builds is quite enough. I’ll stick to buildings that don’t need permissions such as gazebos or chicken sheds!”
Many thanks to Kim Siu of Get Rugged and the Hobbit Hideaway for sharing with me this honest, warts-and-all story of a phenomenal build.
There really is no better foundation for a natural build than the rubble trench. Tried and true, it beats concrete hands down in terms of cost and drainage. You can read exactly how to build one here, but basically it’s a trench, in this case lined with geotextile membrane, and filled with stones and rubble. That’s it.
As with most straw bale structures, you throw up the post and beam structure first. That includes the roof. The straw bales are basically the infill for the walls. The advantage of constructing your roof first is that you have this wonderful sheltered area to store materials, use as a shelter, and work within.
I asked Kim how she went about obtaining those elusive building permits. This isn’t her first house and we documented the UK permit process in detail in a post on Kim’s other larger straw bale house.
“Getting planning permission and the building warrant followed exactly the same procedures as our other house,” explains Kim. “It was far easier this time though, as we had an architect that not only knew his stuff, but knew how to communicate with officialdom. Sam at Rocket Architects restored my faith in architects! He got us through all the permissions gracefully, without too much stress.”
The Building Team
Kim employed an alternative building firm in the UK called Hartwyn to build this gorgeous house. Yes, you don’t have to do it yourself, and there are some definite advantages for getting a professional in.
“Hartwyn commission Rocket Architects as part of their package. That’s one of the reasons that we chose them for our project, because we knew we needed to jump through many, many hoops. Especially as this build was a hardcore eco-house,” says Kim. “Hartwyn were the natural builders and educators. Another reason why we chose them was because they would recruit and teach students as part of the build. This was such a great fit for my vision of the build and how it could be beneficial to others.”
Yes, it was a wonderful concept. I followed the process online and found it heart-warming to see the next generation of builders being trained in another, more sustainable construction methodology. You can see plenty of photos of the students at work with Hartwyn on the Get Rugged Facebook page. It all looked great fun.
Where did Kim find out about Hartwyn? “Ah from Talking Natural Homes,” she says. When talking to Jeffrey (the Natural Builder) it was very obvious that our values were aligned and it was a no-brainer to choose Hartwyn.”
The Toughest Part of the Build
During the building of the main structure, things move along at a nice clip. Motivation is high, and something is blooming out of nothing. That’s the easier part, in my opinion. I think the toughest section of any project is the finishing. Everyone is tired. Money is running out. And plastering and detailing are trickier and more time-consuming than you think. Kim, it seems, would agree.
“I think the final stages where the most difficult as they sapped me of all energy. There was just so much detailing left to finish. We had several months left of sanding, sealing, scraping, painting, fixing and finishing to get it ready and this seemed to take forever. I was under so much pressure at the time as my mother was dying, and we had got into huge debt with the build and needed to get it rented out and bringing in money as soon as possible.”
What would Kim do differently next time?
This is where Kim said there wouldn’t be a next time. :)) “It’s the financial pressures and permissions that took the most out of me. I’m still knackered. Who knows though, a few years down the line and I may well be looking at an earthbag structure. I think if I did build again, it would be with earth and stone...”
He he he, watch this space. :)
5 great lessons to take away from this:
The Hobbit Hideaway now
Kim’s hobbit house is now the most beautiful little bed and breakfast cottage where it gives people the chance to taste what life is really like inside a bonafide natural home. Guests continually come away shiny-eyed and rejuvenated. If you’d like to know more about it, or book a stay, look here. https://www.facebook.com/hobbithideaway/
Photos by Dewi Roberts
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Far up north, there’s a bard in the woods creating dream worlds for himself out of timber and earthbags. He’s built a cabin, a yurt and a hobbit house in his quest to escape the drudge of the wage economy. Let me introduce the free spirit that is Hugh Morshead.
“Ten years ago, I moved into a one-room cabin in the woods. I thought that I would be living a life of voluntary simplicity with one boot in the 19th century and the other in the 21st,” Hugh explained to me. “After my first summer the bank called. The manager met me at the door and asked if she could sit in on the meeting. Across the desk I faced two sets of arched eyebrows. Their concern was my sudden wealth...I paraphrased the money lender in David Copperfield – disposable income equals income minus expenses.”
Disposable income equals income minus expenses. Stick that on a billboard, someone! Whenever I read all these ludicrous “How to earn a million bucks” stories, I’m prone to chuckle or sigh depending on my mood. Yeah, earn a million and spend 900,000 in the process, not to mention selling your soul, your health and your peace of mind. Hugh’s philosophy is mine. Reduce your expenses, love the Earth and her creatures, tell stories and create beauty.
Now, I’m not going to recount Hugh’s tale, because he’s written that himself and will do a far better job than I. But I’ll whet your appetites with a summary.
Born in Ireland in 1953, and having spent most of his twenties backpacking, I think we can safely say Hugh has always possessed a touch of wanderlust. He emigrated to Canada in 1980 to build equestrian cross-country courses, and for 30 years ran a horse farm with his wife.
Then ten years ago they divorced.
I always think wherever you are in the world, divorce is poorly treated. There are no proper ceremonies or celebrations, because the staid judgement of society is that a divorce is some kind of failure. I would very much question that idea. Divorces are major successes, they are the victory of the individual soul over the expectations of the herd and the temptations of the comfort zone. They are beginnings, the time to dust off old dreams and live them to the full.
So, in true Thoreau style, Hugh left his old world and moved into a 150 year old log cabin on a spacious property in the woods in Ontario. “I went on a crazy building spree – sauna, earthbag hobbit house, yurt, greenhouses, gardens, root cellar, sheds, ponds,” he says. Thus began his new life. “I divided the year into three: reading and writing in winter, working and building during the summer and travel by bicycle or on foot in the autumn.” Now if that doesn’t make you consider going it alone, I don’t know what will. :)
One earthbag house after another
Then somewhat later, ‘on a whim’ as he describes it, Hugh built an earthbag house for himself. It cost him just $500 to construct, and was semi-submerged beneath the ground. He lived in it for a year, and described the experience as much of a spiritual journey as a physical one.
The thing with mud homes is they are as infectious as smallpox, so naturally earthbag building didn’t end buried in the woods for Hugh. “My neighbour had a similar whim,” he says, “so I built one for her. Then I got a call to go to Australia for a month and build one for indigenous women elders.”
I always think building with mud takes you places you never thought you’d go. The dirt opens doors and paves new ways. So off Hugh trotted halfway round the world, from the northern cool of Canada to the Pacific heat of Australia, to build yet another earthbag dwelling for The Sacred Womyn’s Camp near Byron Bay. “It is a collection of tents in the bush...home to Lois Cook, the eldest surviving member of the local aboriginal tribe and designated as Custodian of Country.”
That story of Hugh’s experience with the Sacred Womyn’s Camp is a beautiful one that he recounts in his book, which will be available soon.
Which shelter is best?
Having built a variety of sustainable shelters, I asked Hugh which kind of structure he preferred and why. “I believe earthbag building is simply the best form of owner-build home for any environment,” he says. “Yurts are a perfect starter home or guest house, and combined with an earth plaster wall they have great potential – less work, less materials and easily built by one person.”
Why do we love earthbag?
I’ve often noticed that people are smitten by earthbag. I am too, still. It’s so simple and solid a technique, and so so sustainable, because in the right climate you can actually get away with zero timber. It’s solid, earthquake and hurricane proof, fireproof, bulletproof and soundproof. You can create gorgeous organic shapes with earthbag, too.
As you may have already gleaned, despite his appetite from freedom, Hugh is incredibly socially-minded. He is involved in his community through public speaking, a farmer’s market, and workshops. While the workshops are open to all, the emphasis is to empower women and indigenous people to build their own ultra-low-cost homes.
This summer he’s at it again. He will be up to his knees in dirt in a workshop in Canada organized by an indigenous Elder, Becky BigCanoe who lives on Georgia Island on Lake Simcoe in Ontario, Canada. The course will take place on indigenous land and the plan is to build a hobbit house and a yurt over a few weekends in July and August. I’ll be posting details of it in the newsletter when it’s finalised, but heck if I were in Canada, I’d go!
Hugh is very helpful and sociable. "I'm always available to answer questions," he says. You can read more about his lifestyle and building projects, or contact him from his blog: http://hughmorshead.blogspot.com/
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