Natural Elements promotes the use of environmentally sustainable projects wherever possible. When providing advice on materials we consider the following factors when selecting sustainable materials:
Natural sustainable materials that can replenish themselves such as bamboo, hemp, timber and straw bale can be the most ecologically sensitive option and can provide a building with a beautiful look and feel.
When timber is used on a project, we are very careful in selecting products that are come from sustainable harvesting. We avoid using timber from native and old growth forests or unsustainable/unethical timber plantations. The Natural Elements advisory team includes a number of experts in Sustainable Timber procurement, so we are well equipped with the knowledge and industry experience to make positive choices when it comes to timber selection.
For more information on sourcing sustainable timber, visit the Mullum Creek Timbers Guide.
Embodied Energy / Life Cycle Embodied Energy
Embodied energy is the amount of energy consumed by the processes required to produce a building material, from extraction to processing, to manufacturing and installing on site.
Materials such as aluminium and steel have extremely high embodied energy, however they can last a long time and be recycled.
Materials such as concrete have low embodied energy relative to aluminium, however because concrete is used in such high quantities (8 billion tonne each year), the overall embodied energy for concrete is very large.
Embodied Energy is not easy to calculate. Natural Elements can assist you in understanding how materials differ in their embodied energy.
Choosing to incorporate recycled materials is a great way to reduce the environmental impacts of a building because it lessens the amount of materials going to land fill and it reduces the demand on virgin materials and our earth’s resources.
In Victoria around 40% of landfill waste is from the construction industry. We really need to stop our buildings ending up at the tip by designing good quality long lasting buildings with components that can be recycled at the end of the building’s life cycle.
Sick Building Syndrome is rife in many buildings due to high carbon dioxide levels, mould growth and pollutants entering interior spaces. As our buildings are becoming more energy efficient and sealed up, we need to consider the health of the interior environment more than ever.
One method of ensuring healthy interiors is through adequate ventilation, which can be done through a Heat Recovery Ventilation System and opening windows very regularly.
Another aspect of healthy interiors is choosing insulation and furnishing materials that have low levels of harmful volatile chemicals and ensuring the construction systems do not promote internal mould growth.
A good resource detailing harmful chemicals in building material is the Living Building Challenge’s Red List.
Thermal Performance Properties
In Victoria we want our building envelopes to retain heat in winter and not in summer, therefore the building envelope should be made up of materials that have good insulative properties. Materials that insulate well are often light, such as bulk insulation, rigid board insulation and strawbale.
Materials that are poor insulators tend to be heavy and dense, such as rammed earth, stone and brick. These materials hold heat and allow heat to move through the wall. If thermal mass materials are being used for an external wall, heat will escape through these walls in winter and will enter the building in summer and therefore these heavy materials are not ideal as external walls in Victoria’s climate.
When choosing external materials, it’s very important that we consider the thermal properties and how they can enhance or hinder the passive heating and cooling of a building.
We strive to consider the maintenance aspects of a material. Will it need to be replaced or repainted every few years? Replacing a low embodied energy material multiple times can end up being no more efficient than choosing a higher embodied energy material that will last a very long time and can be recycled. Natural Elements believes that it’s important to discuss maintenance requirements with their clients early in the design process, to ensure clients are aware of the how much attention and care the building will need in the future.
The best way to reduce the environmental impacts of a home is to build less and use less materials. Australian houses are the largest in the world averaging at, nearly triple the average house size in China. Moreover, according to the latest Census data an average Australian homes have one spare bedroom.
Natural Elements advocates for building less and utilising space in innovative and creative ways.
Haar P (2019), Mullum Creek Timbers Guide, Mullum Creek Housing Development Guidelines
Li R.Y.M., Du H. (2015) Sustainable Construction Waste Management in Australia: A Motivation Perspective. In: Construction Safety and Waste Management, Risk Engineering, Springer, Cham
Watts J, 'Concrete, the most destructive material on the earth', The Guardian.
Wilson L, How bis is a house, http://shrinkthatfootprint.com/how-big-is-a-house