Last April 2015, a massive earthquake devastated many parts of Nepal with 600,00 buildings. It is very exciting to hear the efforts of Nripal Adhikary and his group Abari who are promoting a safe, sustainable and cost effective method of rebuilding.
Their aim is to use local available materials as well as labour! “The benefit of using bamboo is that once treated it is durable, as strong as steel, but flexible. Rammed earth walls are extremely strong and last a long time,” said Adhikary in a recent article in the Nepali Times.
Said Adhikary: “The main challenge about alternative earthquake resistant housing is to change the mindset. We have been able to change the people’s mindset but we are still waiting on the policy makers.”
Abari have also build a school with open source plans for a school design using earth and bamboo which you can find at this link.
A recent post in the influential blog inhabitat has a showcase of “Solar-powered Bush House exemplifies chic eco-friendly living in the Australian outback.”
Designed by archterra architects in Western Australia, (not built by us) it is great to see their simple but contemporary design gain international attention for their sustainable approach. They have used a long east west axis, good cross ventilation and appropriate shading devices.
“Two rammed earth walls and a concrete floor slab help retain thermal mass” which is an excellent approach. I think its thermal performance can be improved a little by replacing the south facing rammed earth walls a more insulated walls system. This would reduce the winter heat loss through these southern walls that never receive solar gain. You could then utilise more rammed earth internally.
Internally positioned rammed earth is the best performing position as it is thermally isolated from the outside climate. This then gives you options in summer to cross ventilated during the cooler night and isolated it from the hot day time temperature. In winter the walls will absorb the winter solar gain from the great solar passive design and also any additional warmth introduced from the fireplace. These internal walls are great for regulating the diurnal (day vs night) temperature and are more efficient at regulating the humidity.
archterra architects also have a good focus on the environmental impact of each material “Life cycle cost analysis carried out by etool can provide an in-depth analysis of your buildings carbon footprint and comparison agains an ‘average’ equivalent building with respect to materials and energy input/output.”
Recently featured in the Newcastle Morning Herald was a house we worked on couple of years ago. It was great job as the design by Mark Lawler Architects was a tjermally efficient use of rammed earth.
The owner researched rammed earth extensively in a quest for a construction method that offered ultimate natural thermal and aesthetic benefits.
“Its thickness as a single skin allows it to be both an external and internal finish.”
“Combined with the concrete floor slab, the rammed earth walls provide great thermal mass.”
“Arranging windows with north-facing glazing in all living areas and locating service rooms such as the garage, laundry and bathroom on the western sides of the home also enhanced the thermal efficiency and comfort.” Read the full article at this link.
We have been enjoying the solar passive design on our current project at Wamberal on the central coast of NSW. It has a long east west axis and loads of internal 500mm thick rammed earth walls… plus heaps of cross ventilation pathways. On top of this will be an amazing origami like roof line that will twisted and bend up to the north to let the winter sun in. The warm of the winter sun is called APRICITY….. which some might call a luxury but we think should be standard feature.
3D Printed earth buildings are not new, but when Ronald Rael of eartharchitecture and professor of architecture at the Uni of California in Berkley starts pressing “print” on his computer, things get interesting. He is using clay, sand and salt among other materials to print out panels and blocks of earth. It looks very sci fi and artistic yet at the same time has links to African Mosques and middle eastern architecture.
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n this printed house sand is used for the modular bricks and 3D salt is used for the glass. Quite an interesting concept especially with the green walls. There are more images at emerging objects.
As discussed recently in New Scientist, “for Rael, building with earth has simply been updated. On his Instagram feed, he uses the hashtag #dataclay to describe this mesmerising confluence of computer-based fabrication and good old, fingernail-crusting clay.”
“Clay and salt – as well as resin, nylon and sand – can now be squeezed out precisely in layers to form complex, interlocking geometric shapes. Whether you call them bricks, modules or components, it is earth architecture reborn, filtered through algorithms and high-tech machines.”
One of emerging objects ideas is the cool brick that borrows from the ancient technique of the Muscatese Evaporative cooling window. This would be ideal for hot dry climates and would replace reliance on expensive and resource consuming air conditioners. It would also provide a much nicer environment for the occupants.
New Scientist “Then there’s the Quake Column, an earthquake-resistant structure built from interlocking 3D-printed sand blocks. Inspired by ancient Incan construction, the angular blocks are designed to shift and resettle after a seismic event, unlike the rigid cemented-together rectangular blocks of most modern buildings.”
A major problem with 3D printed dwellings is that might take away local employment. “Indeed, one of Emerging Objects’ fundamental axioms is that the surge of interest in architectural-scale 3D printing has been waylaid by an unnecessary search for ever-larger printers. A building-sized printer might produce a building-sized object, but thinking in terms of individual components, not whole buildings, is the way to go, says Rael. Scale the product, not the printer.”
In world where the usability of the latest mobile Phone is more important than the usability of our houses, it was refreshing to read the following article. ‘The Australian’ newspaper’s Christopher Allen refers to the current exhibition in Sydney in his article: Superhouse exhibition takes architecture beyond the McMansion. It’s hard not to admire some of the amazing houses in what is arguably the most decadent art form. I especially liked the Pierre house.
Chris had this to say in summary. “The project of the so-called superhouse is thus implicitly counter-cultural. In a world preoccupied with materialism and the tokens of success, with fashion and opinionated chatter, with the addiction to mass media noise and superficial arousal of every kind, it proposes silence, peace and serenity.”
“It would be interesting to follow this exhibition with another on houses that achieve simplicity of design, sympathetic relations to their setting and openness to nature on a minimal budget. It must be possible to design something beautiful and harmonious without massive amounts of reinforced concrete and complex feats of engineering. It would be fascinating to see what can be done with recycled timber, mud bricks or even rendered Besser bricks, corrugated iron and other vernacular materials.”
“Sliding or removable walls, or heavy walls of materials such as rammed earth to provide insulation — depending of the orientation of the house — and much higher ceilings than in standard suburban houses to allow heat to rise and escape through clerestory windows, would all be relatively inexpensive ways to cope with the Australian environment without resorting to airconditioning, which is surely incompatible with true architectural ambition.”
Long live the artist who can create good form AND function. See the full article here.
Energy-Saving Design: Investigation of the Thermal Performance of Rammed Earth Residential Buildings
October 20, 2015
Luke Mahony
Earth Dwellings Australia, with the the University of Western Australia and the Department of Housing are investigating the ACTUAL performance of rammed earth houses. “Numerical and experimental investigations available in the literature show contradictory results. Factors such as hydroscopic behaviour, that is the ability of the wall to control indoor humidity, and how the house is used by residents are not adequately treated in current decision frameworks and policies. ”
Two identical houses have been built in Kalgoolie, both are rammed earth except one has insulated panels inside the rammed earth. There are sensors placed throughout the houses and walls measuring temperature and relative humidity. There is now a website showing details of the project and preliminary results. The aim is to measure the thermal performance of occupied rammed earth houses.
The preliminary results make very interesting reading. “Although insulation is effective at separating the inner and outer parts of the walls, comparing results for the monolithic and insulated houses shows something quite unexpected. There is no real difference between the room or ceiling temperatures in both houses. Both houses show a roughly steady internal temperature of around 20 to 25 degrees even when subjected to a sudden cold snap which occured on the 15 November 2014. Although the temperatures in the walls dropped, this heat was successfully transferred in to the house so internal air temperatures remained largely unchanged. Some questions therefore need to be asked about how these houses perform, specifically why the inclusion of insulation does not affect air temperatures inside the house. A possible explanation might be that the non-rammed earth part of the houses’ envelopes around the kitchen, bathroom and the roof, are ultimately controlling internal temperature. Another might be that thermal bridges in the insulated rammed earth walls where the insulation was not present, for example around windows, allowed heat to bypass the insulation entirely. These questions are being investigated as part of the ongoing project.”
I love it how an ancient, common building method has become popular and a luxury item. Hopefully some of the one third of the worlds population living in earth houses read this article or watch this video below, they may want to stay in their earth houses instead of moving into ‘modern’ inefficient cultural-less boxes.
This video shines a spotlight on how we live on this island Earth and suggests we need to move with the Earth’s Rhythms. Whilst the movies focus is on the important topic of food production, building our dwellings in relation to the earth’s Day/Night and Summer/Winter rhythms makes perfect sense, and helps us become ‘deeply in-tune with nature’.
Internal Rammed Earth Sydney NSW
This 6 meter high rammed earth wall we recently built on the Northern Beaches of Sydney NSW, is located in the middle of the house. It will serve as great thermal regulator. As thermal mass is slow moving, it evens out the daily temperature curve. Being internal it allows it to be cross ventilated in summer by sea breezes, whilst in winter it will store any heat from solar gains or heating and act like a hot water bottle. The only thermal mass better than rammed earth is water.
A recent article in the conversation talks about the benefits of radiant heat, which is an important feature of rammed earth. “……we knew that, at the low wind speeds typical of offices, radiant heat exchange mattered more than convective heat exchange. In other words, radiation temperature is more important for thermal comfort than air temperature. You could argue that offices should have wall conditioners, rather than air conditioners.” This is yet another reason to include internal rammed earth.
Internal Rammed Earth Sydney NSW
If you open a fridge that is empty, all the cool air will fall out, but if the fridge is full (same as thermal mass) the coolth stays inside the fridge. It is the same principle for ovens and same principle for houses. This is why internal thermal mass is so effective.
Earth Dwellings 