When an Earth House home achieves one star above the 6 star requirement, this means it uses approximately 20% less energy to run. That's cold hard cash that stays in your pocket. The added bonus is that this will reduce the carbon output by around 1 tonne per year, primarily from heating and cooling. Another tonne of carbon can be saved by using efficient appliances, such as LED lighting and other energy saving devices. By using a solar powered energy system that supplies energy back to the grid, you could save in excess of 4 tonnes of carbon annually.
The benefits of double glazed windows for energy savings is well known, which is why Earth House Australia only installs double glazed windows in our homes. As well as saving energy, you'll save energy costs and reduce noise entering your home.
Insulation is an important component of any home. Generally, we use either earth-wool or polyester batts in internal walls and the roof space. The R value is specific to each project, but a minimum of R2.7 is used for the internal walls and for the roof space it is R4-R6. Occasionally, we may use a compressed material of high R value in the roof if the cavity does not allow for standard insulation.
Thermal mass is extremely important in a home as it moderates the external temperature variances. The thermal mass in an Earth House is high thanks to the rammed earth walling coupled with a concrete slab. Uninsulated rammed earth is generally 300mm thick and naturally provides excellent insulation properties, but Earth House has developed an insulated system that allows for an even higher R value.
Thermal mass can also be improved by ensuring correct orientation in design, and by placing windows to allow the concrete slab to be gently heated by the winter sun and shaded from the harsh summer sun.
LED globes are used where possible, as they use up to 5 times less power than halogen globes. Recessed downlights can be installed. We use downlight covers to help reduce heat loss through the necessary removal of insulation around these lights.
ORIENTATION AND LAYOUT
Orientation is the most important component of a building design. The solar aspect of the design is crucial and will lead to lower energy consumption and greater comfort in the long term. The layout of your home is also critical so it is important to make sure you have thoroughly considered your options. The floor plan of your home is extremely important, not only with regard to the flow of your home but also with how you plan to use your home. The design needs to maximise not only the solar aspect, but any views or outlooks. A carefully considered design will cost less in the long term and give the comfort, beauty and sustainability we all desire.