These are some areas of research that may be undertaken. Some need immediate attention and some are desirable. Other areas of research will be considered if they further the aims of EBAA.
Energy Efficiency of earth homes
EBAA and earth builders generally support government initiatives that address global warming, green house gas emissions and sustainable building generally. Historically we have always leaded the way. Many people who chose earth for building did so for the very reasons of energy efficiency, thermal comfort, natural conditioning and low embodied energy. We support changes being addressed in REPATS to remove obvious flaws and look at the benefits of thermal mass.
The focus of REPATS or Residential Energy Performance Assessment Tools (First rate, NatHers etc.) has been to concentrate on insulation to reduce heating and cooling of buildings. To look at buildings as sealed insulated boxes. This approach will definitely make a difference to the energy efficiency of lightweight constructions such as all timber-framed building including brick veneer. These REPATS have had some real problems
Earth has an average to poor “R” or insulating value but excellent “Y” value or capacity to store heat (warmth or coolth) known as thermal mass. It is the combination of these values and its ability to control humidity that results in the comfort experienced in earth buildings. We need to provide scientific data to support anecdotal evidence that earth buildings offer comfort efficiently or we need to explore and measure proven ways of improving performance without loosing the inherent qualities, aesthetics and economy of earth building.
We may have to do research into what does constitute thermal comfort. Does thermal comfort only exist between 21 and 25 degrees C?
Do people have the same perception of thermal comfort in all climates and in all seasons?
Earth building shines large in this area that is not being considered by government legislation presently but will necessarily be on the sustainable building agenda within a decade. We need to study this attribute and use it to our advantage in promotion of earth building.
Low cost sustainable housing with earth
Earth building is labour intensive though requires very little fossil based energy for processing and curing is solar. The material is widely available. Earth building is appropriate, sustainable and sun dried and can be recycled endlessly so it is also renewable technology.
Australia has a crisis with providing low cost housing. It is nothing like the problem that poor countries face. It is in the interest of world peace and sustainability that poorer nations don’t abandon earth building to emulate our unsustainable living standards.
It is the responsibility of wealthy nations like ours to share our experience in providing safe, durable and comfortable housing using earth.
Building for earthquakes
Standards Australia is currently looking into revising the Standard to be presented to the Australian Building Codes Board for inclusion in the Building Code of Australia.
Australia is not considered a country prone to earthquakes though we do have a history of weak tremors through to medium/high level quakes measuring over 6 on the Richter scale. Evidence from Newcastle (NSW), Meckering in (WA) and New Zealand quakes suggest that earth buildings coped well when compared with those built with more conventional building materials. No earth building in Australia is known to have been condemned or destroyed by earthquake and no loss of life has been recorded. Well constructed earth wall homes should according to International standards have no damage in tremors, survive and be repairable in medium quakes and be damaged beyond repair but not pose a threat to life in large quakes. Contrary to public belief some well constructed earth buildings constructed in countries with a long history of earth quakes do survive massive quakes whilst poorly constructed buildings of concrete and steel collapse with such devastating loss of life as recorded in Pakistan recently.
We need to test buildings built using the methods outlined in the EBAA’s publication Building With Earth Brick & Rammed Earth in Australia, 2004 to prove they will withstand the likely moderate quakes we experience in Australia and that they perform as required by all Authorities.
If necessary we may need to improve the methods and specification used and undertake engineering to provide details and tables to be used by designers, building inspectors and builders.
We need to provide data, specification and manuals to poorer countries building makeshift shelters to minimise loss of life. If they can’t afford to build well-constructed earth homes they certainly can’t afford to build in concrete and steel even to a poor standard.
We need to locate records of what buildings were damaged or survived and the casualties relating to overseas earthquakes to reinforce our contention that well constructed earth homes can be used successfully in earthquake prone regions.
Building in bushfire prone areas
Earth buildings have excellent fire ratings (4 hours in the case of 250mm thick mudbrick wall). This makes them suitable for building in bushfire prone areas and for the construction of fire rated walls within buildings. Studies of detailing of wall to roof junctions and timber posts and door jambs in walls may provide useful information in any proposed revision of the EBAA Earth Building Book. This information will be good for promotion of earth.
Building healthy homes with earth
Sick Building Syndrome, toxic building materials and finishes, air conditioning, noise infiltration and electromagnetic radiation are all problems associated with modern buildings. These problems are largely lessened or eliminated in buildings of unfired earth.
Passive solar designed naturally conditioned earth buildings offer a healthy alternative. The moderation of temperature by thermal mass negates summer cooling requirements and in many instances the need for air-conditioning. Sound transmission figures for earth are very good offering an interior quietness and stillness that produces calm.
The natural materials are non-toxic and non-allergenic if finished with natural paints readily available for earth.
German studies reveal that earthen walls actually moderate the humidity within the building adding to comfort levels, they even will take up and filter toxins from the out gassing of plastics used in such things as computers and will shield electromagnetic radiation.
We need to further study and independently verify these proven findings and undertake research for Australian buildings and conditions.