Easy form

By last night we had cut and made four sections of shutter board with backing frames and the means to connect them to each other. And today we did our first test to find out whether they erect easily and if the joints are flush when erected. We were also anxious to find out if it was possible to work within the cavity to compact the earth. One concern was that 450mm was too narrow a space in which to operate and that this would undermine the levels of compaction.

We managed to set up the forms very easily. The alignment was not a problem and the panels bolted together as we had hoped. With a battery operated screwdriver the assembly was quick and painless. Each section, although heavy and rigid, can be lifted and erected quite easily by two people, which was a surprise. Fortunately the 450mm wide space is sufficient to operate within and this should not compromise the rammed earth compaction rates. However we will have to make a step ladder for the tamping team to use to get into (or out of) the assembled formwork especially when it is over 3m in height. And of course the pipe clamps worked a treat. They are simple robust units that I am sure may develop legs and walk if not carefully looked after.

We had planned to make three sets of formwork so that in any one day:

1. one would be compacted and curing,
2. a second would be in the process of being filled and compacted and
3. a third would be in the process of being erected.

After today's test, it might just be possible to get away with two sets. At the end of a day the cured set could be disassembled and the next morning erected before the compaction process began. But let's not get ahead of ourselves - there is still a long road ahead and next week will be dedicated to eradicating alien vegetation and to building forms. But for me, its off to stunning Mozambique with family and friends for a short holiday.

On Form

The shutter board and wood for the backing frame to make the formwork arrived and during the past two days we have been putting the Festool to work. The wood came from a local supplier and the timber has been treated which is certainly going to give us problems - it's quite wet and I'm sure it will warp when it dries. Even the Festool doesn't like it but these things happen.

The best part is that it's a big Meccano set. And we have plug-in tools that create a huge mess and make a lot of noise! As an aside and by the end of the day there is something to show for all the work. We're making something! Fantastic.

We even have to rush out to buy other essential bits and pieces so we're satisfying the shopping urge and we're learning something in the process. For instance, it's much cheaper to buy long lengths of galvanised pipe than it is to buy custom short lengths. In fact, it's so much cheaper that you can buy all the kit to thread the pipe and pay someone to thread it and still be up. Except that it's almost impossible to find the bits and pieces to clamp and thread the pipe as this is now all so passé. Galvanised is out and plastic is in and the problem here is that plastic pipe does not work that well in a pipe clamp. So we have cut, drilled, clamped, hammered, screwed, rested and screwed some more. What a day! Boys and their plug-in toys. Highly recommended and now we're in top form.

House Plan

Initially we had decided to go big and build into this big house 'green' things. The theory behind this was to show people that modern & invariably big houses can exist and don't have to be plugged full time into the various national grids. This would not have been particularly sensitive to a whole lot of green issues. New is not green and neither is big. Also this whole process is a complete experiment and it was a fairly risky choice to have made so we reverted to plan 'B', which was small. But there is small and there is small. The idea was to build a 250 square meter house that included a double garage and three bedrooms. A tv lounge would then double up as a guest room. But this house has a lot of women who have many needs I have since discovered they have the power of the veto. So the idea that our teenage daughter, who is currently away from home would not have a bedroom on her return and would have to stay in the tv/guest room was rapidly discarded. When the TV was relegated to the single communal space which meant the possible permanent din of poor content, I became quite inventive in trying to avoid that possibility. Of course the cars got evicted because they don't have an opinion and now the garage is the tv room come teenage hangout room. So we have gone from big to small and 'small'.

To view the plan of the house, click here. It's the latest version I have and it honestly does not date back to 2005. And there have been a few additional changes. How this will translate into an actual living space will be interesting. It will be very light and airy. But as can be expected, talk of a planted roof and rammed earth outer walls have raised quite a bit of interest. I just need to grow my hair and start talking to the plants and the scene will be set - and anything else that may appear unusual will invariably fit right in.

Borehole

Today has been quite interesting. I've never witnessed a borehole being drilled and today was a first.

What was most surprising was the rate at which the shaft is sunk. It moves rapidly, especially through the soil section. When it finally hits rock it slows quite a bit, but it still continues at an even pace. Throughout the process, a compressed air and water mix powered by a massive compressor is blown out of the drilling bit forcing all the debris up and out of the hole. As it gets deeper, the increasing ground water makes the mix wetter and a fine mud slurry develops. The noise of this all is quite intense, especially when the hydraulic hammer kicks in.

Samples of the ejected material are kept and it gives quite an interesting view of whats below ground. Initially the soil is very red, which is the red tacky clay we have everywhere. Below that is a decomposing granite which is yellow in colour. This was the material that the engineer recommended we build the house out of, except that it's inaccessible. Then there is granite where the slurry colour changes to a blue grey. This is apparently what we want to be boring through with the hope of encountering a fracture or fault line, which is where all the water is.

One of the problems we had was that the wall started to collapse into the hole. Apparently they like to get some sense of the volume of water that the borehole will deliver before they put in the steel sleeve. This way if the hole ends up being dry, which happened to my neighbour and others in the area then the costs have been to some extent mitigated. However, this was not an option and the operator had a feeling that he was busy eroding a cavern below his rig and was concerned about the risk of a major collapse. So the decision was made to install the sleeve that protects against collapsing side walls before there was any guarantee of water. The sleeve (or casing) is a steel pipe that comes in 6m sections. As each length is lowered into the ground, the next length is butt welded to the buried section and this is done as many times as is required until the bedrock is reached. In total we installed approximately 30m of sleeve. The bottom three sections of sleeve had been perforated to allow water to seep into the pipe. To prevent these clogging, several bags of fine stone were finally poured into the gap between the sleeve and the drilled hole. Apparently this also promotes movement of water in and around the borehole.

The plan is to drill until the hole is 70m deep. By the end of day one, we were at 50m and the feeling was positive with evidence of water and a good 'recovery' - I suppose that means that water is flowing fairly freely into the borehole and that we have a sustainable supply. However, this is a guess and without a proper test the yield will remain a mystery. What is important is that it delivers water and in sufficient quantities to tide us over the building period and then through any periods where we run out of harvested rainwater.

Next on the agenda is to get the pump installed and operational. That includes an automatic switch that will keep our reservoir full and all the various protective circuitry. Hopefully then our immediate water issues will be resolved.

Water Divining

Water is obviously quite a big deal. Globally, and in the near future it is likely to become one of the greatest threats to our existence and building in an area where potable water is fairly scarce places it high on my agenda. Issues of water borne diseases (cholera) and contaminated drinking supplies just adds to the problems. Banks don't want to finance properties where water is absent and it is one of those things you need to have to secure a bond. The idea is to harvest rain water - eventually. But to establish a site, people need water to function so there is an immediate need. Since we haven't started harvesting rain water and since banks won't rely on the heavens to underwrite our water needs, we have to find an alternative supply. Being fairly rural means drilling for it so we need to do some divining - of sorts.

Dowsing, sometimes called divining, doodlebugging (in the US), or (when searching specifically for water) water finding or water witching, is a practice that attempts to locate hidden water wells, buried metals or ores, gemstones, or other objects as well as currents of earth radiation without the use of scientific apparatus. A Y- or L-shaped twig or rod is sometimes used during dowsing, although some dowsers use other equipment or no equipment at all. This is dreamcatching stuff and frankly I'm not willing to bet my water budget on a piece of willow or a thrown hat, despite how reliable they may be. I did have a choice of "bottels en stokke" (bottles and sticks!) experts but being logical, rational and used to relying on technology i.e something that plugs in, I contacted the 'Resistance Apparatus' chap instead. It took him about 20 minutes to find two suitable sites, which was fantastic, except they were both on the neighbouring property. Charming.

Antonie is the supervisor on site. He's had a run of seriously bad luck and misfortune recently. He moved to the area for work leaving his wife and family at home 400km away. Shortly after arriving, he had to rush home to his wife and family when all of his dogs and cats were killed using the infamous 'two step'. On the commute back, he managed to T-bone a taxi that jumped a red light and now he thinks he's got tick bite fever. But he seems to be fairly optimistic and is to be able to do everything. He's even got expensive taste and wants me to invest in a 'Festool' circular saw, the most expensive circular saw imaginable - but apparently it can cut quite a straight edge and will be perfect for our formwork. His dad was a boilermaker and had a natural gift for finding water. He even managed to find water with the throw of a hat! So Antonie decided to apply his mind to this new task and with a glass Coke bottle filled and corked, he decided to map the property. Of course, he confirmed that the resistance apparatus had correctly found water. He even did it with his eyes closed and the bottle tipped before he fell in the hole. Despite this, Antonie went on to find water all over the place. In fact I could have saved myself quite a bit in trenching and in pipework and labour had Antonie decided to do his bottle act sooner. Thanks Antonie - and now I'm off to invest in a rose quartz garden and dreamcatchers.

What & Why

This is a short summary about what we are doing and why...

The principle idea is to be low energy and self sufficient as possible. The motivation behind this is a theory of peaking resources and peaking energy supplies. This will inevitably result in increased resource and energy costs and the focus of this project is to mitigate against these increases. Specifically regarding energy, there are many groups focusing on addressing this and raising awareness around this issue. Amongst them include ASPO, the Energy Bulletin and The Oil Drum all web based publications. Chris Martenson has a Youtube hosted 'Crash Course' Series and Chapters 17a, 17b and 17c deal with peak oil and related subjects. Overall this series offers an interesting spin to the industrial age and the issues it faces. Other sites address sustainability issues including the permaculture movement. Many publications and books also are challenging the way in which we live, calling for a dramatic change to the de facto standard and a return to a simpler existence. A specific reference to what changes we need to considered is offered by Power of Community. They have an interesting book and DVD on offer that illustrates quite graphically the challenges we face and how we can adapt to them.

Energy Efficiency

Principally there are two issues around energy. The first is embodied energy - the energy needed to create something and the second is the ongoing energy demand - the energy to maintain it. For instance a Prius motor car probably uses the same amount of embodied energy to make as does any similar car so it is not particular efficient in that regard. But it consumes far less energy (fuel) to operate than does a similar sized non-hybrid car. This energy audit can apply to almost everything. Embodied energy is one of the motivators for the recycling movement - rather reuse something than manufacture it from new. It's about energy and unnecessary energy consumption. And energy consumption in general has a significant environmental cost.

Reducing energy consumption can be simply achieved by a few simple design changes. Obviously, from a purist point of view, building a new house is not 'green' as the embodied energy in an existing house has already been 'spent' and is consequently much less than building a new house. The 'greenest' solution is to upgrade an existing building, but I am willing to sacrifice the embodied energy costs in an attempt to reduce future energy demands. A bit like buying a Prius.

Other attempts to reduce energy include:

• building in an accessible location, accessible to town and work. This will reduce transport costs.
• Positioning and orientating the house to achieve a cool house in summer and a warm house in winter using only sustainable heating or cooling.
  
• Being 'off grid' regarding food. If most of one's food can be locally grown i.e. in one's own garden, this represents a massive energy reduction especially as modern farming methods rely heavily on fossil fuels for pesticide, fertiliser and mechanisation.
• Using solar or renewable energy sources to heat wherever possible.
• Using solar to generate electricity - we do not have a suitable hydro option which would have been much cheaper and more reliable.

House Design
We're southern hemisphere based so the house needs to be north facing.

To reduce the early morning and late afternoon heat from the low sun angles, the house needs to be narrow on the eastern and western facades. By choosing a reasonable roof overhang (eave), the high summer sun can be excluded from the house during the bulk of the day in summer and deciduous trees can be planted on the eastern and western sides. The trees will help screen the house from the low sun angles.

In winter, the sun travels fairly low in the sky and will heat the house throughout the day, especially when the deciduous trees have lost their leaves. The roof eaves will not inhibit the winter sun from entering the house. Therefore the extent of the eaves are of critical importance.

This simple design element reduces the need for cooling in summer and heating in winter.

Other Design Aspects
By building thick walls increases the thermal mass of the walls. Rammed earth is perfectly suited to this and the outside wall thickness of the house will be 450mm. These walls will take a significant amount of time to heat up and cool down. The theory is that any heat that was absorbed during the day will be slowly released during the night. This promotes a fairly constant temperature within the house throughout the day.

We will be using a planted roof. This will be resting on a concrete slab and the combined thickness of the slab, soil and vegetation will act as a huge blanket over the house. This too will promote an even temperature within the house.

Underfloor heating/cooling will be provided by way of a pipe buried in the floor. To heat the house, hot water will be pumped through the pipe and cold water when cooling is required. The hot water will come from solar hot water unit supplemented by a wood burning stove and the cold water will come from a 600m pipe buried in the ground outside the house. The ground temperature remains fairly constant and a buried pipe makes use of the significant thermal mass of the earth to cool the water in the pipe.

Heat loss through windows is currently being investigated and I am researching the possibility of installing double glazing. This is an overkill where I live, but the benefits are great soundproofing, great thermal insulation and even offer a slightly improved level of security. In combination with Mediterranean shutters, the heat loss through windows and doors will be greatly reduced and the security greatly enhanced.

Finally, the stand has been cut into the slope so the rear of the house will appear almost 'buried' and the front will have a most stunning uninterrupted view with huge windows. This should reduce the effect of the prevailing wind and will also hopefully contribute to an even temperature throughout the year.

Offgrid Items
Water
Potable water will come from a borehole and harvested rainwater. To reduce water consumption, grey water will be treated and reused in the cisterns. Surplus grey water will drain into the food forest/vegetable garden. A well illustrated concept of greywater recycling is included in the design of Earthships by Michael Reynolds.

Food
There is quite a movement in our house to get off red meat, much to my horror. From a sustainability point of view this is a fairly essential step. A red meat eating commuter on a bicycle is less environmentally friendly than a vegetarian in a four wheel drive!

The intention on this front is to develop a food forest. Apparently the food yields are comparable between a food forest and a modern commercial monocultured crop. The benefit of a food forest is that it has several layers of food whereas a monocultured crop does not. A specific benefit of food forests is that they take little effort to maintain - 'forests look after themselves'. Predators abound and diversity of species is a fairly key requirement. There are a couple of interesting links worth watching in this regard. The first is A Natural World: A Farm for the Future by Rebecca Hoskings and the other is Establish Eden (Food Forest) With Love by Geoff Lawton. The plan is to plant between 500 and 1000 indigenous and exotic plants. Most will provide food in one form or another. What has been interesting is trying to research indigenous food sources. A useful source of information has come from 'The Lost Crops of Africa' book series published by The National Academies Press. They have a volume that focuses on each of the following: Grains, Vegetables and Fruits. All of the volumes can be downloaded in a pdf format for free or purchased at great expense. Not being an expert on much, I have managed to convince Neil Fishwick who runs a local indigenous nursery to advise me in this regard. Currently I am getting holes dug and have to organise 30 tons of 'kraal' manure - the stuff that is not full of ungerminated seeds.

These are my main points of focus in trying to reduce my energy footprint. As I rediscover the old ways of how we do things today - and are things that I can implement, I will update this post accordingly. I am sure it will include chickens, fish and any number of other interesting things. But in the meantime it's holes and manure.

Rammed Earth Learning Curve

It started with an idea, then quite a bit of web research, a few books and finally several attempts to put all the theory into practice. But rammed earth is all about the soil, at least initially.

There are two distinct types of subsoil on the property - that soil in which organic matter is largely absent. One is red and has a high clay content. It is generally full of fine material and is not suitable without significant additives. The other, which is more yellow in colour, has a broader set of grain sizes, less clay and is far better suited to this application with a bit of stabilisation.

In an attempt to get a better understanding of rammed earth, we built a very simple, rough and ready wall using a 'Finnbuilder'. Using 8% Portland Cement, I was surprised how solid it was. I accept it looks pathetic, but structurally it was surprisingly strong.

The next attempt was using a small custom-built form that was 750mm long, 1250mm high and 300mm wide. This was a very basic system made from components exclusively available from the local hardware store. We thought the first finished wall using this formwork was stunning. Each rammed layer was distinct and the idea of this finish over a 6m wall was a dream. Again 8% Portland Cement was used and the wall was solid. As a second test, a smaller wall was built without any cement stabilisation. The soil used in these tests was not ideal for this application and when trying to hand compact them, the soil was tacky and stuck to the compactor resulting in a fairly ineffective tool that needed cleaning after every layer. It was messy, time consuming and frustrating. But at the time it did look good.

Both of these walls have since been through a very wet rainy season without any protection. The stabilised wall is showing slight signs of weathering but otherwise retains its shape, looks and hardness. The unstabilised wall has developed dramatic cracks (it has a high clay content) and is probably less effective now than a newly laid mud wall. It breaks off in clumps and is soft to touch. Also, termites would decimate it if it came to their attention and termites are prevalent on this site.

After this very early attempt at building the wall, a soil analysis was performed. Fortunately as part of the process, they did a site visit and found 'better' soil. Better was an understatement as it performed stunningly when compacted. It compacted to a clean, solid & even surface and did not at all attach to the compactor. Also the colour was completely different and made our original wall (that we thought was stunning) look rather ordinary. In fact it looked pitted and worn in comparison. As we did not have enough to fill the form, we began mixing it with some of the red soil and the effect was marvellous without detracting from the ramming properties at all. By mixing colours will allow a few interesting effects to be included in the finish of the final house.

An issue that has since developed is that the wall crumbles! By rubbing it at the corners or sharp edges causes a rapid degradation of the wall - it literally crumbles off in a fine powder. Apparently this is due to oxidation and the best way to deal with this is to seal the wall. Traditionally this was done with boiled linseed oil - I read that somewhere, and the next wall that we built using the imported soil (see Getting Started) was sealed using a modern commercial sealant that addressed this problem. The water just pools on the top surface and runs off without any hint of being absorbed. The only place where water ingress is evident is at the base (as can be seen in the photo on the left) and it is being sucked up from beneath. However, in the final build, the walls will be resting on a stem wall that will keep the rammed earth wall clear of any pools of water or damp surfaces. Also a damp course layer will assist in this regard.

One thing that does become very evident is that the quality of each wall seems to get significantly better than the previous one. Clearly this method of building needs a bit of experience added in to achieve the best results.

For the techies: hydrated lime otherwise known as road lime - Ca(OH)2 has been recommended for stabilisation instead of cement. All the test walls that have been built to date have used 8% Portland cement for stabilisation. Instead a 4% mix of hydrated lime has been recommended as the ICL (initial consumption of lime) from the lab tests was 2%.

The next ramming project is to build a final test wall using hydrated lime and then onto the real thing. The equipment is on order to sieve, mix and convey the soil in bulk quantities. So too is the wood for the formwork. The pipe clamps have arrived and the project is developing a head of steam. But before all of this, I need to sink a borehole and get water on the site. Man needs water before labour. I also have a food forest I need to finalise the planning and planting of...and to sort the water to irrigate the trees.

Getting Started

Everything is quite simple when laid out on a piece of paper. It takes on a life of its own when the idea is put into practice.

My intention is to build a rammed earth house. This is a simple idea and rammed earth houses have been built for millennia. It's just a matter of taking some locally occurring soil, stabilising it a bit and then ramming it into a form in the shape of a wall and hey presto, the wall exists. So I used the soil that was immediately available and built a couple of test walls. Obviously I want to use a soil that will result in a stunning looking wall. Finding 'suitable' soil also means that an engineer who specialises in soil analysis (geotechnical stuff) does a set of tests on the sample and tells you whether it will work or not. Included in the advice is the amount of road lime (hydrated lime) and moisture (water) that should be added to achieve the maximum compaction and stabilisation. This I did and the fortunate thing was that the soil was available on the property, despite our first sample not being suitable at all - and then the problems began. The soil was near the river and extracting it would have affected the riverine/wetland area and this in itself ruled it out. However before the environmental opinion, extracting soil is the equivalent of mining and here I need a mining license. Despite my title deed permitting me to do this, I was advised that many government Acts run in 'parallel' so despite having permission in one forum does not mean I have all the permissions necessary. Any bureaucratic hurdles in a non-functioning bureaucracy is akin to achieving the impossible, so the decision was taken to import the soil from a registered borrow-pit. And this we have now done and today 9 June, we received the last delivery of around 300 six cubic metre loads - which is enough to build several houses.

Besides counting trucks, we have laid electricity and piping for water and irrigation. The property is 300m long and down the centre we have ripped a trench about four feet deep. Into this we have put two electrical supplies - one from the town supply and a second that will come from the proposed solar farm. Every house (we may build a few and develop a small intentional community) will have a combination of the two supplies and hopefully when the town supply crashes, which it is prone to do, then we will have an alternate 'green' supply. On the water reticulation front, there is a borehole pipe, a drinking water supply line, a rainwater harvesting line and an irrigation line from the local watercourse. Buried deeper is a geothermal cooling loop which is a big experiment. Where I live tends to get quite hot (not compared to Kuwait) and we are looking at using a buried cooling pipe to provide cooling to the house. Whether this will work or not is subject to debate which will be finalised when it is tested.

Being an empty plot, a few roads needed to be cut. These will be compacted and then paved with grass pavers, the type that are open to permit grass to take root and allow water to seep into the ground rather than run off at 90 miles an hour. I am mentoring three young men who are busy making these on site, which is resulting in quite a significant cost saving while at the same time setting them up in what I hope will be a successful, though small business.

With all of this activity, the site looks a mess. In fact it is quite a shock as to the extent of the work that has been done, especially the digging and scraping. I have used mechanised equipment to cut and dig and the power of these machines is quite something to behold. To do this by hand would take several hundred hours and many months and I just wonder how people built houses without the limitless power of what we have at our disposal. Certainly they would not have cut it into the slope as I have done, but I hope the house when complete with its planted roof will not be visible to the neighbours and will require a minimal amount of energy to run. But the proof of the pudding will be in the eating.