Sunday, 28 February 2010

Building with earth

Earth. That stuff all around us. The skin of our planet, residue of incalcuable eons of rocks, trees, bugs, fungi and a vast array of other living things squishing together to make this medium for life itself.

I've always thought of it as something we use to grow plants in, or on building sites we move it out of the way to make room for "modern" building materials - cement foundations, brick walls, cement-based plasters and the like. But how about actually building our houses with earth?

Mud huts in Africa spring to mind, or cave-like domes to keep the evening coolness over scorching day, in arid Arabian deserts. But what about here in chilly Europe with our incessent rain? Is it even an option?
It seems so: Ken Neal showed us how with his cob-house in the South of England. Amazing: just add straw and stamp it down, and up the walls soared. Ken's a cob-maestro from those parts, and says that this type of building was normal in times past, in Europe since the 12th century... His cob-house shown here on the left, detail below on right.

Cob houses are one of so many ways of building with earth, the mind boggles at how little we knows about it. OK, there is a small but growing number of builders and crafts-people out there who are working with natural building materials. But the mainstream building industry is almost completely unaware of these options. As I happen to live in a modern society I want to know which other earth-building options there are that might be suitable, in our temperate climate.

OK so there's earth-bag building, brought to public recognition by Nader Khalili of the Cal-Earth Institute. These links show it all: basically a way of making domed buildings with circles of earth in bags. Plastered inside and out with more earth, or a bit of lime for more rainy climes.

Rammed earth is another one, used a lot in the South of Portugal. Also used by the CAT in Wales in a big scale for their new "institute for sustainable education". I've heard it is really labour intensive, like cob buildings, so maybe not that suitable for our renovation where we are surrounded in granite rock. The point about rammed earth and the bagged-wall system is that they offer huge thermal mass, like a house built from rock does: cool in summer, warm in winter (as long as you've got a nice stove or something warming it up). This does not mean it has insulative capacities: unless you put something with fibres and air-gaps in it, like straw.

In fact because rock and wood is readily available here, and straw bale too (nearby Ourense in Galicia). We're thinking of using straw for any new extensions, to be covered outside in a lime render, internally with earth plaster. Which bring us to the other application of earth in building: as a plastering material. (In this case, the straw provides mega insulation, the plaster lends some thermal mass, if you slap it on thick enough).

Somehow, over the last 100 years or so of industrialisation, we have seen cement-based plasters taking over the internal plastering show. This great book gives a full summary of all the possibilities available to us, from clay, gypsum, to straw-clay and so on.

From this book, being at CAT, our own experiences and so on, here's a few reasons why I think earth plasters are so much better than cement:

1. Beathability: cement plaster and walls don't breath, so it's like living in a plastic box unless you have a really well built and managed ventilation system. Earth (and lime) walls allow vapours out but stop water coming in. Like gortex.

2. Economics: if you have a clay based earth in your area it's free, thus cheaper than cement.

3. Environment: Manufacturing a tonne of cement produces a tonne of carbon dioxide into our already choked atmosphere. Plus transport, distribution, sprawling factories, mountains carved up to extract the raw material. It burns your hands, stings your eyes, ruins your tools. Nightmare. Earth does none of these things and at the end of it's life an earth house can be turned back into garden.

4. Easy to work with: no need to pay specialist builders when you can do it with your mates and family.

5. Wood rot factor. We have found that any wood elements in our house that had been surrounded in cement plaster or external render was completely rotted. In contrast, where they had left the earth&lime plaster over wooden walls, the wood was still in perfect condition, after maybe a hundred years. I guess it is like putting your foot in a plastic bag to keep it dry, compared to a sock.

So last weekend Miriem asked if we would come and help with some earth plastering in her wee house in the Galician mountains we said "Sure". As discussed above, in theory it makes sense, now we need the experience. Either way, we like the idea of helping out with other natural building projects in this area. In fact there's a kind of network of folk between Galicia and North Portugal that get together fairly regularly to help each other out. So it was that Kira and I volunteered to represent our family, and off we went.

First off, we needed the material. Earth with a high clay content. It so happens that we've got loads of this right around our place in Troporiz, so Miriem, Frederic, Bugui and other Miriem came for some digging.

This is top spot (we found that day). No stones, high clay content (about 30%). Cool colour...

Quick cup of tea, with Madam Kiwi. Shared with Miriem and Frederico

Then onwards to Miriem's hill-top house, where the gathering of the Galician clans had begun.
Miriem decided she wanted an insulating plaster, to warm the place up a bit (or rather, to hold the warmth in a while longer). Earth plaster itself can be pretty straight forward: 30% clay, 70% sand and aggregates, water. Add straw to the mix and it beefs it up, giving it some insulative qualities. How much, I don't know. I suppose it depends on how thick you make your plastering. Adding straw makes it a cob mix (like Ken's house, or our pizza oven).

Miriem's house (on the right)

This kind of cob is usually made by piling straw together with the clay-rich earth and stamping on it, walking, squishing it together, to make sure the components are nicely mixed. As the snow was still fresh on the nearby hills, it was way to chilly to take off our boots and stomp around in a chilly mix. So in rolled the cement mixer, which we brought up from Troporiz.

The mix was more or less like this: 12 buckets of earth (about 35% clay content), 1 box of straw cut small, and 2 buckets of hydrated lime. Miriem decided to add the lime to help the plaster avoid build up of bacteria or fungi, which can happen in humid environments.

Straw cutting crew at work

Then we get it on the walls:) This we did in various ways, forming balls and hurling them at the walls, which they stick to wonderfully, or just applying it like you would any plaster.

Bugui (bearded) and César (with glasses) the leading Galician expert in straw bale and natural materials building, also seriously active with solar ovens, the Spanish strawbale network and permaculture projects.

Kira and Pedro (another Portuguese rep) soaking the stone walls in prep for the plaster.

Then Kira makes plaster lumps for Frederico...

The final picture: 3 walls, first layer of plaster on. I think another "finishing coat", smoother, no added straw, might come next. Some rock left exposed on the edges. Not sure if these won't be like cold panels during the sub-zero winter months, but we'll have to see.

After work and much merry feasting, we decided we seriously needed a hot shower or bath, so we headed for the local thermal springs... (scalding secret spot well worth knowing about!)

A great day all round. Pilar, from Santiago de Compostela was inspired to pen this sonnet which sums it all up in far more eloquent ways than I can muster:

Corrido de los muros

(Ritmo: carabina 30 30)

Caminito a Covelo

Pa´cer el muro de Miriam

El arco iris ilumina

El corazón en la partida

Si un muro quieres revocar

Con los medios a tu alcance

Cal, barro y paja cortada

Constituyen buen aislante

Si arcilla buscas decantar

Y así saber su pureza

Con agua la has de mezclar

Que repose en la cubeta

1º Estribillo

Un gran arco iris en el cielo azul

Una hormigonera en la furgoneta

Un montón de manos y muchos amigos

Revocas el muro con menos pereza

Para darle consistencia

A la mezcla en cuestión

Busca mierda de caballo

Refuerza la solución

Mierda de vaca o caballo

De oveja no es suficiente

De cerdo no es solución

La nuestra no es eficiente

2º Estribillo

Si un nuevo mañana tu quieres construir

Una hormigonera en la furgoneta

Paja, cal y barro bien amasados

Y un montón de manos que apliquen la mezcla

Mucha gente agobiada

Por tremendas hipotecas

Así es como se lo montan

Pa comerte la cabeza

Un cobijo sostenible

Una vida sin dilemas

Mira oye qué estás a tiempo

De salirte del sistema

2º Estribillo

Si un nuevo mañana tu quieres construir

Una hormigonera en la furgoneta

Paja, cal y barro bien amasados

Y un montón de manos que apliquen la mezcla

Cuando trabajes en grupo

Revocando la pared

Recuerda la norma, compadre

Cerrar ojos y boca a la vez

Gafas son agradecidas

Guantes protegen también

Piensa que en boca cerrada

Ni moscas ni barro entran bien

2º Estribillo

Si un nuevo mañana tu quieres construir

Una hormigonera en la furgoneta

Paja, cal y barro bien amasados

Y un montón de manos que apliquen la mezcla

Tras un día de trabajo

Con la luna en creciente

El descanso es merecido

Termas y agua caliente

Pero maldada es la suerte

Que la terma está chapada

Mas recursos no nos faltan

Manos y una gran cizalla

3º Estribillo

Si un grandioso día tu quieres construir

Mete la cizalla en la furgoneta

Un montón de manos y muchas sonrisas

Rompen las cadenas con más firmeza

Qué cosas tiene la vida

Permacultura aplicada

Paja, barro y cal mezcladas

Luna y pelota picada

Ultimos estribillos y conclusión

Si un grandioso día tu quieres construir

Un nuevo mañana, una tarde, una noche

Un buen revoque, un muro, una casa

Mete todas estas cosas en el coche...

Un gran arco iris en los corazones

Las herramientas en la furgoneta

Un montón de manos y muchos amigos

Afrontas los muros con menos pereza

Thursday, 25 February 2010

Ecological economics

Great talk here by long term Greenpeacer, Rex Weyler. If you have an hour, watch. Interested to know what you think

Google vids don't seem to link across. But try this link:

Wednesday, 17 February 2010

In the Stone Room

Sometimes wonder what's the point of having a completely independent say-what-I-want site, then never actually use it but to post a few family snaps. Pathetic. So much going on, so many issues, ideas, great thoughts (or fools' illusions), crises local and global to discuss, to share, to link to. And what happens? Nothing.

Is this blog a diary of a few events that I have encountered - or a platform to issue forth my take on the world around us? Clearly the former so far, but I am tempted to paddle into those more hefty questions that surround us every day: new economic paradigms, imminent peak oil, climate chaos (and denial campaigning), bothched agriculture policies, misguided humanitarian aid and recovery programmes, the general head-in-the-sand mindset of our generation, the lack of fresh cream in town, the irrelevance of our kids´ school curricula and the lack of alternatives save us quitting everything we do so we can teach them from home and generally withdraw from the local community. Long breath. These and many more. (That was nice, making a huge long list, with total disregard to grammar, syntax and flow, just because I can). If you're still reading you are part of a tiny droplet of humanity that is, and for this, I salute you.

So I sucumb: The happenings of our life. Here's some stuff from November last year. Which reminds me of another thing (last distraction for this post, honest) :Why be compelled to sticking to the chronological order of things. This happened today, or this month. To hell with that! Loads of stuff happened to us like 8 years ago, or 3. Or last year. When I have an inspiration I'm going to get it out, like it or not.

So where were we? November, a few months back. Hywel visted from England to lend some wisdom on dry stane walling, working with lime and straw building. (Here seen playing with wood too, maybe just because he's not allowed to at home, or too busy on lime courses, but here with our elven friend (Paulo) building a wee woodshed on upper camp.

We went a bit mental with the front gate and, at João's insistence took it to pieces (with his new stone-block-moving toy), expanded the entire entrance way so we drive in and be nice lazy modern shoppers. Principally however I suspect was so João could drive in easier with his truck loads of rock or whatever and not carry it from the road. In any case, we took down the wall, shifted untold tonnes of earth into Vitor's tractor (to top of land, a future workload of Eygptian proportions) then rebuilt the wall under Hywel's all-knowing eye, all dry stane and solid.

Hywel and Paulo were keen to show off their lime skills. Little wonder, it's amazing stuff, which I'll blether about in another post. Our task at hand: pointing. Test the "cal viva" or active, living lime (what do you guys call it again?) which costs a paltry 6 euros for a 40 kg bag. We mixed it with sand: 5.5 sand to 1 of lime. And water. Let it fizzle and pop awhile and boom: we had our first pointing mix. Kira, seeing something new happening (finally!) insists on being in on the scene, grabs a pointing trowel, shoves us out of the way and takes centre stage in front of our new tutor.

The key, Hywel explains, is to maintain moisture for a couple of weeks after application. Not too hard in late autumn, though summertime we'll need a hesion sheet and regular spraying. João - local stonemason, cement disciple - monitored progress closely. He complained (of course) but mostly about our haphazard depths of pointing. He liked the material. I think. Time will tell. Anyway, we like it, so there.

Nikita picked it all up really quickly, as per usual (annoyingly quickly I have to add).

What else? Lots of stone washing. This is a whole new excuse to dress up as a Jedi and wield a purring staff, threatening to soak the enemy to death with a micro touch on the 180 bar trigger; Ungh - melted Jabba, you will make.

Our task: clean earth, lime and cement debris off the walls that have been buried below a concrete render for the past 50 years or so. First, chip the bloody cement off the damn wall (this is a nightmare not really worth telling).

Anyway, fun had by all till it gets really boring. Then you just keep going. Good machine though.

Downstairs sala (more like a dungeon) came up lovely. Actually all we had to do was to wash off centuries of pig shit and cow-hide, then a few more recent decades of more civilised workshop use (by former owner Senhor Felix Rodrigues and his watch-fixing obsession people keep telling me about). Directly upstairs, the main rooms, also stripped of internal plaster, ready for a good wash. Ceiling gone, almost ready for the roof to come off, new one on, and all that house building stuff that seems to be an impossible mirage (delays caused by local planning office taking forever to give permissions, and national roads authorities blah blah).

To end this stony post, some more glimpses of the new-old walls...

Enough of Kira posing. Here's two other fanatics - mushroom fans. Fungi Freaks. Nuts...

Have to admit these parasols tasted pretty good when cooked right. Though you'd need a couple of kilos to satisfy this pair first.

Saturday, 6 February 2010

Week in the life of Casa Felix

January has been as busy as any other, though we still don't have planning permission so can't actually start work on the house. So we have spent way more time working the soil, which is mostly a gritty, sandy affair, high in acid and not very productive. So this is has become one of our tasks here, one of my obsessions even.

Arguably one of the most important things we have to do globally: figure out how to make soils productive without importing
fertiliser, using herbicides or pesticides
(all of which are made from fossil fuels) .
Here Kira's on our new raised beds, made in the chicken's former home, so we thought it must be fairly well fertilised. More on this design later.

This month Aljo visited. Former skateboarding conquestor, skate pad inventor, mountain bike builder and traveller. It's been a long time since last we connected, and in fact Alj represents the the first of my board-riding mates to visit.

Loads happened. First: moving dirt (see left). Their had to be a better way to move a few tonnes of this stuff from "up" to lower down the land where I want to build a new terrace for planting bamboo.

So we build a ramp to cross three terraces. With chipboard kindly flowed by Maria Fuentes (Galician sawmill).

OK this took a day or so of labour, but I swear it will save time later. Anyway it was quite surfable...

Here the chickens decided they had to give design advice, but just ended up getting in the way.

Next we decided to build a wall to stop catch the falling earth, creating the next terrace at the same time.

Then we went down to our river / watermills area to cut some chestnut and alder trees - for building projects later in the year. We are following local advice on felling trees at the "minguente" or the waning moon of January - when the sap is at rest, it means the wood will be better for all kinds of uses, be less vulnerable to bugs and diseases, will warp less, etc.

These chestnuts were first spotted by Hywel, who is big on coppicing. Cut them, he urged, and they'll grow back. In fact they had proabably emerged from the stump of an old chestut, cut about 15 years ago. I climbed up to tie a rope way up each tree, so Aljo could put tension on the rope, to help the tree fall the right way. The bark comes off easily, newly felled. Aljo's paw showing the girth of this one, only 10 years old. We'll probably use it as a post for a new outdoor kitchen outside the main house.

Then it rained. So we took refuge in this local river-cave.

Back up for air (to the terraces on the hill) we transplanted an olive:

Mulched trees to prevent weed growth (robbing nutrients from their second year of growth. Under the cardboard we chucked in some composted chicken and sawdust manure. Above it, we've now added forest leaves, straw and anything else we find lying around that's organic and soft (no more spiky things, like I foolishy laid around them last year).

Back at the camp, we revisited the slowest-to-build solar heating system in history. We need to build a frame around this panel now to enclose the 4m2 glazed double-doors we were given. More on this sytem later - when we get it finished...

Meanwhile, under strict instructions from Charlie and Lyra (the cats) the chickens are tractoring away on the lower terrace. See how much they have "ploughed" in just over a week. We move the cage every couple of days or so. Potatoes and peas following shortly behind in Feb.

Just as Aljo thought he could take a break, we whisked him away for weekend labours: clearing the local community youth club's tennis court. Yes: a tennis court! (OMG). And yes we can use it, and yes they definitely want people who are any good at the game to come and teach local kids how to play. In fact this local youth club is just kicking off again after a few years absence. I've been asked to be part of it in some way, so hopefully we'll have lots of opportunities to share ideas, games and projects with them, local kids and families soon.

Of course clearing this abandoned court /football pitch meant we had a source of oak and pine leaf litter, from year. Perfect for that tree mulch job:)

Finally we have all become servants to the cats, who need to be moved from house to land every day (we still live off site).
Here Charlie, clearly irritated by our delays growled "Are we leaving yet or What?"