8 Sustainable Building Materials
Any prospective home builder who listens to sustainable construction advice should know about the choices in building materials that are environmentally friendly. Timber is the traditional material used for the frame or the house, but unless it is sourced carefully it is not always an eco friendly choice. Trees are a renewable resource, but most take a long time to become mature enough to cut for building a house. However, pine grows more quickly and you can source timber from dedicated pine plantations.
Here are some more building material options you may not have thought of –
- Many people choose concrete for their whole house instead of just the flooring slab. It has good thermal mass, meaning it has the ability to keep the home at a stable temperature so there is less need for heating and cooling.
- ICF blocks are an Australian invention originating from thermacell blocks. Corner and wall blocks are assembled on site to create a complete wall.
- Mudbricks are ideal for building on a large block or property where there is plenty of clay available. The clay is mixed with soil, straw and/or cement to help reinforce it and pressed into moulds to set. They can be taken out before they are dry and left to finish drying in the sun while another batch is placed into the moulds.
- Strawbale material is somewhat similar to the above only bales of straw are stacked up to form the walls, shaped, stabilised with steel pins and then covered with mud or a cement based render.
- Timbercrete is a relatively new building material consisting of sawdust mixed with concrete. It produces a material ideal for building which is stronger than concrete on its own and much lighter, with a very high thermal mass.
- Rapidwall is made from fibreglass reinforced gypsum plaster that is water resistant. The walls – which can be up to 12×3 metres – are prefabricated and must be lifted into place with a crane.
- Clay bricks are a common building material that is attractive, but surprisingly has little thermal mass value when used for external walls. However, if used inside the they offer thermal mass ability, absorbing and storing heat to create a stable temperature.
- Rammed earth is another way of building a home using natural materials. Earth is mixed with the right amounts of gravel, sand, clay and cement and often, waterproofing additives. The mixture is machine-rammed into removable formwork to create an immensely strong wall capable of load-bearing.
Not all of these options will suit everyone, but it is good to know what is available apart from timber, which has traditionally been used not only for the frame, but to line both the inside and outside walls of homes.