Organic buildings use abundant and renewable organic materials such as wood, straw, bamboo, cellulose fibre insulation, and natural paints, oils and waxes to create low energy buildings which breathe. A great variety of organic building styles have been developed by different cultures over many centuries. Modern technology can be used to create new styles suitable for city and rural living in different parts of the world.

The consumption of fossil fuels over the last 150 years has allowed the widespread use of inorganic building materials such as concrete, steel, aluminium, fibreglass, and brick. These inorganic materials are man made and require the use of considerable quantities of non renewable energy, giving off the greenhouse gas, carbon dioxide. Organic materials on the other hand grow from seeds, absorb carbon dioxide from the atmosphere as they grow, and store the carbon within the building structure.

Building construction, and the running and maintenance of buildings uses a high proportion of the world's fossil fuel energy. In 1992, buildings accounted for 48% of the United Kingdom's total energy usage, and 46% of the U.K.'s carbon dioxide emissions. Buildings use less energy in New Zealand, but still account for 22% of total energy use. Building designers need to be aware of the energy use and greenhouse gas emissions of their buildings. In New Zealand, the most common new house construction only contains about 5% of renewable organic materials by weight, with the other 95% made up of energy intensive inorganic materials. Organic building designers can reverse this ratio, so that up to 95% of a building materials can be organic and renewable.

Organic materials have the ability to breathe, and absorb and give off moisture, creating a healthy indoor environment. Organic buildings have much in common with organic foods, with emphasis on health, energy efficiency, and sustainability. Organic farmers question the consumption of fast foods promoted by multinational corporations, just as organic builders question the use of convenience building materials promoted by large organisations.

Many important aspects of building materials, and building design are often overlooked. An organic building sustainability index has been created to compare the sustainability of building materials and designs over the life of the building. The index is simply the number of years before the total CO2 emissions of the building equals the carbon dioxide stored in the structure of the building. The total emissions include the energy to heat, cool and ventilate the building as well as the energy to create the building materials. The index shows that if enough readily available, renewable organic building materials are used in conjunction with a smaller amount of inorganic materials, and the building is designed for long life and deconstruction, then a high sustainability index such as 300 (300 years) can be achieved..

Organic building, using the sustainability index, allows a great range of choice in building styles, and a chance to break away from the standardised inorganic designs.

The purpose of Organicbuilding.com is to promote the health, energy efficiency and sustainability of organic building design. This will be done through web links to others involved with organic materials, organic design, energy efficiency, health, sustainability, and concern about global warming.