These criteria used for defining green products was excerpted from "Building Materials: What Makes a Product Green?" as featured by Environmental Building News.
Aside from salvaged or recycled content, there are a number of other ways that products can contribute to the conservation of natural resources. These include products that serve a function using less material than the standard solution, products that are especially durable and therefore won't need replacement as often, products made from FSC-certified wood, and products made from rapidly renewable resources.
Products meeting this criteria may not be distinctly green on their own but are included in GreenSpec because of resource efficiency benefits that they make possible. For example, drywall clips allow the elimination of corner studs, engineered stair stringers reduce lumber waste, pier foundation systems minimize concrete use, and concrete pigments can turn concrete slabs into attractive finished floors, eliminating the need for conventional finish flooring.
These products are environmentally attractive because they need to be replaced less frequently, or their maintenance has very low impact. Sometimes, durability is a contributing factor to the green designation but not enough to distinguish the product as green on its own. This criterion is highly variable by product type. Included in this category are such products as fiber-cement siding, fiberglass windows, slate shingles, and vitrified-clay waste pipe.
Third-party forest certification, based on standards developed by the Forest Stewardship Council (FSC), is the best way to ensure that wood products come from well-managed forests. Wood products must go through a chain-of-custody certification process to carry an FSC stamp. Manufactured wood products can meet the FSC certification requirements with less than 100% certified wood content through percentage-based claims. With a few special-case exceptions, any nonsalvaged solid-wood product and most other wood products must be FSC-certified to be included in GreenSpec. A few manufactured wood products, including engineered lumber and particleboard or MDF, can be included if they have other environmental advantages, such as absence of formaldehyde binders. Engineered wood products in GreenSpec do not qualify by virtue of their resource efficiency benefits alone (for more on this, see EBN Vol. 8, No. 11).
Rapidly renewable materials are distinguished from wood by the shorter harvest rotation, typically 10 years or less. They are biodegradable, often (but not always) low in VOC emissions, and generally produced from agricultural crops. Because sunlight is generally the primary energy input (via photosynthesis), these products may be less energy-intensive to produce, though transportation and processing energy use must be considered. Examples include linoleum, form-release agents made from plant oils, natural paints, geotextile fabrics from coir and jute, cork, and such textiles as organic cotton, wool, and sisal. Note that not all rapidly renewable materials are included in GreenSpec, non-organic cotton, for example, is highly pesticide-intensive. In some cases, even though a product qualifies for GreenSpec by virtue of its natural raw materials, it may have negatives that render it inappropriate for certain uses, such as high VOC levels that cause problems for people with chemical sensitivities.