To identify the most environmentally responsible building material, the choice would logically rest on two fundamental principles:
- It is a renewable resource.
- It is a biodegradable resource.
Wood is the only common building material that satisfies those criteria. Measured against plastic, steel, aluminum, concrete, or cloth, wood is the most environmentally friendly in terms of low emissions, energy consumption and toxic by-products. Every part of the tree has a use.
Trees are mostly carbon. The carbon comes from the carbon dioxide (CO2) in the atmosphere, and through the process of photosynthesis is converted to wood fiber. This carbon is “fixed” in the wood, and can only be released if the wood is burned or allowed to rot above ground. A young growing forest helps to balance the excess carbon dioxide in our atmosphere. This is an ongoing renewable natural process.
The definition of “green” is different from person to person, but eco-friendly building materials are pretty easy to identify. The material should satisfy at least two cornerstones of environmental responsibility: renewable and biodegradable. Remarkably, in your average home, wood is the only qualifier (or more broadly, anything plant-based). When grown in a responsible and sustainable manner, wood, cork, and bamboo pretty much cover all the bases. Cork and bamboo are easier to evaluate since they have a limited growing range and are not bio-diverse. Wood is more difficult as forests yielding species appropriate for hardwood flooring occur all over the world, with different criteria constituting responsible silviculture. The farther from home, the more one has to depend on third party certification to verify an environmental pedigree. The most widely accepted and respected criteria for wood comes from a world-wide non-profit organization called the Forest Stewardship Council (FSC for short). To quote their web site (fsc.org): FSC was “established in 1993 as a response to concerns over global deforestation… and through democratic process effects solutions to the pressures facing the world’s forests and forest-dependent communities.” Wood deserves the extra scrutiny since healthy forests are necessary for human survival.
What is often left out of the conversation is nearly every other element of the building, especially by comparison to wood (or bamboo, cork etc.), qualifies as an environmental disaster. For instance, the world’s yearly cement production of 1.6 billion tons accounts for about 7% of the global loading of carbon dioxide into the atmosphere. Portland cement, the principal hydraulic cement in use today, is not only one of the most energy-intensive materials of construction but also is responsible for a large amount of greenhouse gases.
Anything plastic is deleterious to the environment in every respect from cradle to grave and beyond. Vinyl, plastic laminate, PVC pipe are common plastics that will leach poisons in landfills for centuries beyond their lifespan. Plastic residue now outweighs plankton in our oceans.
Glass, any metal, quarried and mined material… they are not renewable or bio-degradable, they consume an enormous amount of energy to extract, fabricate, and transport, they leave a toxic trail in production, and are rarely recycled.
By contrast, wood is: non-toxic; leaves a small footprint in production and transportation; has a long life cycle with low maintenance; sequesters carbon dioxide; and contributes to an environment that does not harbor or promote potential allergens. Every part of the tree is used… there is no “waste” in production. And oh by the way… it’s renewable and bio-degradable. Wood is the most widely used eco-friendly building material with nearly 40% of industrial demand now satisfied by plantations. Plantation-grown does not necessarily translate to earth-friendly especially if the plantation requires unhealthy herbicides and pesticides, and/or if it replaced a diverse forest. Competing land use, like pasture and agriculture, account for more than 90% of forest degradation around the world. The rest can be attributed to development and illegal logging. The UN”s Food and Agriculture Organization’s (FAO) reports consistently that over half the world’s harvest of wood is burned for fuel.
Since green has become popular in mainstream culture, many claims are made including so-called “improvements” to environmentally devastating products, thereby putting them in the company of legitimate eco-friendly materials. Renewable, biodegradable, non-toxic, low energy consumption, and durability… these are the cornerstones of eco-friendly building materials, and wood is the best example.