Rammed Earth: Spotlight on ‘Golden Vale’, Megalong Valley
This month we have award-winning architect Joseph Mammone from J Mammone Architecture shining the spotlight on the incredible sustainable building material, Rammed Earth.
We explore Rammed Earth, how it was utilised at our award-winning ‘Golden Vale’ Megalong Valley project, and the benefits of this incredible material. Enjoy!
Rammed earth: Rammed earth walls are constructed by ramming a mixture of selected aggregates, including gravel, sand, silt, and a small amount of clay, into place between flat panels called formwork. Stabilised rammed earth is a variant of traditional rammed earth that adds a small amount of cement (typically 5–10%) to increase strength and durability. Stabilised rammed earth walls need little added protection but are usually coated with an air-permeable sealer to increase the life of the material.
Rammed Earth in Golden Vale Project:
The material palette also plays an important role in the sustainability of the home. It was important to select materials for the home that would provide the clients and site with the aesthetic identity which it deserved, yet we also had to think about the materials relationship to site and impact on the environment.
Rammed earth was a material decided to use early on in the design process. The clients and ourselves loved the way its formation reflected the rocky escarpment around the site, its incredible tactility and its environmental properties. The soil component of these walls was Basalt, which was sourced from a local quarry in Oberon, as well as gravel, sand and 5% of cement content. The thick 450mm rammed earth walls provide large areas for heat to be absorbed and hence moderate internal temperatures through thermal mass.
The colour of the rammed earth allowed the house to recede into the landscape, while the large panes of glass are able to filter the golden light into the home, and the tactility of the grain and layering movement reflects the natural formation of the surrounding landscape. The colour was created with the use of the natural Basalt rock along with added a small amount of black oxide.
The material palette also plays an important role in the sustainability of the home. It was important to select materials for the home that would provide the clients and site with the aesthetic identity which it deserved, yet we also had to think about the materials relationship to site and impact on the environment.
Sustainability:
The thick 450mm rammed earth walls provide large areas for heat to be absorbed and hence moderate internal temperatures through thermal mass.
The embodied energy of rammed earth is low to moderate. The selected aggregate was chosen from a local quarry to minimise transport emissions. The formwork used for these walls is unlike traditional formwork methods – it is made from recycled plastic and reusable. The speciality lining internally also avoids the needs of a releasing agent.
Rammed Earth construction has great fire and pest resistance. There are no flammable components in a rammed earth wall and its fire resistance is very good. There is no cavity to harbour pests and nothing in the material to attract or support them, so its resistance to pest attack is very high.
Finish:
The rammed earth finish in Golden Vale, was very intentional to reflect the rocky escarpments around the site. The layering in which the walls are placed creates a sense of rhythm and movement in the natural landscape. Also, the wall has been described as having a beautiful tactility to them which can be appreciated from the interior spaces. It was important to showcase the material in both the external and internal spaces. The thickness of the walls creates deep reveals and thresholds with the architecture.
To summarise, the home is the product of intricate detailing, careful craftsmanship and a collaborative relationship between the architect, builder and client.
Looking back at the home now, we truly believe it is an inspiring piece of architecture that has a lasting impact on all - the site, the people and the local community have been transformed by this project. It has become and will remain a memorable point of reference in Megalong Valley.
Joseph Mammone | Principal – Nominated Architect
