Building Ecotopia: Sustainable Homes

by Chuck Hall

The good news with greener building methods is that such techniques are currently in vogue all over the world. The bad news is that many builders make a few changes here or there in standard industrial building techniques and call it ‘green,’ without going nearly far enough towards a truly sustainable building practice. Modern building methods are very taxing on the environment. Cement production is one of the most energy intensive of all industrial manufacturing processes. Cement production now accounts for over 8% of total carbon dioxide emissions from all human activities. Cement kilns in the United States are the third largest source of dioxin contamination. Part of this is due to the fact that kiln operators are allowed to burn toxic wastes as fuel. Concrete trucks require about 500 gallons a day of highly alkaline wash water to operate. This type of water is toxic to fish and other aquatic life.
Steel, another predominant building material, is made from iron ore and other non-renewable resources. Steel production is energy intensive due to the amount of heat required. The fuels used to fire steel forges are also a major source of carbon dioxide and other forms of air pollution.
Vinyl siding and other plastics used in the construction industry are made from non-renewable petroleum by-products. Plastic manufacturing requires toxic chemicals and produces more toxic waste. Plastics don't breathe like natural building materials. Many plastics emit toxic fumes. Some plastics can take up to 50,000 years to deteriorate!
Commercially harvested lumber products are usually treated with preservatives that are highly toxic. For example, arsenic is a component in many pressure-treated lumber products. Commercial forests harvested for lumber often use hazardous pesticides and preservatives. Irresponsible deforestation causes soil erosion, contamination of waterways from silt and pesticide runoff, and loss of biodiversity in the forest ecosphere. Composite wood products such as plywood and other particulate boards are often held together with toxic compounds which in addition to contributing to the degradation of the environment, are suspected to cause allergies and other health problems.
Commercially manufactured building materials cause problems for health and the environment at all stages of their life cycle, from production and manufacturing, to use in building, to disposal when buildings are razed. Additionally, long-distance transportation of building materials contributes heavily to transportation costs, not to mention the additional pollution caused by the large diesel-burning engines required to transport them.
Clearly our current methods of building homes are extremely taxing on the environment! But many natural building techniques go a long way towards promoting more sustainable living. By using materials readily found in nature, building supplies don’t have to be shipped great distances, or manufactured in factories that pollute the environment.
There are many natural building methods. Some of these would include straw bale building, earth bag building, and stone building. While all of these have their advantages, I prefer a method that uses materials readily found on almost any building site: clay, sand and straw. This ancient method is known as ‘cob building.’ Next week we’ll look at this versatile building style.