Rammed earth is a tactile material creating spaces that have a sense of solidity and calm
Rammed Earth Designs
Design For Seasons are experienced in rammed earth designs and the application of rammed earth energy efficient, sustainable homes in WA.
Rammed earth is a natural form of building material, literally coming from the ground with very little processing, making it sustainable and readily available. It is a very tactile material creating spaces that have a sense of solidity and calm. Once the walls are in place there is no extra cladding or finishes required. The rammed earth is the finished wall.
Historically, the use of rammed earth is widely used throughout the world, and since the early 1970’s this building method has been making a resurgence in Western Australia and other parts of Australia. Modern engineering is being applied to structural design, construction methodology and mix of materials, along with clever design to create buildings of beauty and permanence.
In Australia, modern rammed earth is cement stabilised, and often unprotected from the elements. A dry mix of 5 to 10% cement is used as a stabiliser, giving the walls the required strength. Most walls are 250 to 300mm thick and are built in sections length ways up to 3.0m depending on location of openings, and keyed together at the wall junctions, giving an articulated appearance.
The soil mix determines the colour of the walls and can vary from reddish-brown gravel/loam to a light cream coloured limestone, or anything in between from mixing the two. Reconstituted building rubble is another wall mix, making good use of a waste material.
Rammed earth has very high thermal mass, which assists greatly in achieving thermal comfort conditions, both in winter and summer. In winter walls absorb the heat of the day, from well designed passive solar sun direction, and re-radiate it at night when needed to maintain comfortable temperatures. In summer the walls even out the day to night temperature fluctuations, by absorbing unwanted heat during the day. By opening buildings at night stored heat can be released, a process known as “night purging,” allowing heat to be absorbed again the following day.
Rammed earth also has the ability to “breathe” and thus produce a desirable humidity within a space, by absorbing and releasing humidity, balancing the humidity to a level that is comfortable, being not so low as to be dry and unpleasant (40%) and not so high as to also feel overly humid and unpleasant (70%).
Other properties of rammed earth include:
- Nil toxicity
- No cavity (being a monolithic wall there is no hidden place for vermin, insects or mould)
- Regular air changes (being a “breathable wall” allows for the slow exchange of air keeping the interior a healthy space)
- Very high fire resistance
- Recyclable, being crushable and re-usable, with no toxic residue.
- Speed of construction, using materials often from nearby, with very little water needed and potentially nil wastage of water or other ingredients.
Design For Seasons works very closely with rammed earth builders or specialist contractors during the design and building stages to ensure the rammed earth component is built to affordable and achievable industry standards, while allowing for creative and unique wall material mixes, finishes and designs.