Jeff Howe, September 2007

To download this commentary, click here (pdf, 140k).

A significant challenge faced by individuals trying to improve their purchasing habits and trying to “green” their building practices is the difficulty in deciphering which products are truly green and which are not.   Sorting through green claims is important to anyone dedicated to positive environmental change. With this in mind, I offer some simple “DOs” and “DON'Ts” of green purchasing.

Don't substitute for substitution sake! The most common error we see people make is automatically assuming that whatever is currently being done is bad, and thus any new option is better.   This is not necessarily the case.   Many current building practices in the U.S. are actually very good from an environmental point of view and have been driven by improvements in building codes over the past 25 years.   As an example, a certified EnergyStar home may already be the most energy efficient option you can create, even if it wasn't specifically built for “green” purposes.   So, don't change without a clearly defined better option.

Don't substitute ANYTHING for wood products produced either in the U.S. or Canada without a host of research to back that substitution up!   Wood is the only widely available construction material that is renewable and produced using solar energy. We have yet to find very many situations in green building where an alternative material is a better environmental choice.   IF the substitute performs better in the specific function or IF it has aesthetics that are more desirable, THEN you might consider the substitute as long as it has relatively neutral environmental consequences.

Don't assume that a product made with recycled content is a good environmental choice!   Beyond the question of the energy requirements of recycling itself, “recycled content” is frequently just a term used to describe better utilization of the material within a manufacturing plant.   Only post-consumer content really has a significant positive environmental impact.   In addition, and perhaps more importantly, most products with recycled content only contain between 30-50 percent recycled materials.   This means more than 50-70 percent of the product is made from virgin, extracted materials (something that is often forgotten) – and the sourcing of the virgin material is the critical issue.

Do - remember always, that a product is only green in comparison to something else!!   Thus, a product that has 50 percent recycled content can be substituted for one with a lower recycled content (and so on and so forth). But a product that is even 90% recycled steel should not be substituted for most wood products, as that would still suggest an increased demand for steel and all of the negative impacts incumbent with that use.   In general, never substitute a nonrenewable product for a renewable one.

Do - seek out products produced in diverse natural ecosystems, whether it is shade produced coffee or wood products; and the more diverse the better.   Products produced in nonplantation certified forests should be at the top of the “green” list.

Do – be suspicious of agricultural substitutes for existing products.   In a previous article we have discussed the challenges and potentially negative impacts of the industrialization of bamboo.   This issue is no less true for any other agricultural material.

Do - hold agricultural materials to the same level of scrutiny that wood is held. Look for a certified organic label or similar for any agricultural substitute. Industrial agriculture has wide and significant environmental impacts.

Do – buy local and consider “local” even as broadly as from the U.S. and Canada.   Not only are the laws and environmental regulations of both countries extensive and relatively well enforced, but also international shipping and related activities (e.g. ship building and maintenance) are relatively unregulated and/or under-enforced.   Thus there are significant impacts due to the international transport of goods - without even considering the potential social or environmental impacts incurred in the producing countries, which may be substantial as well.

So, despite the seemingly endless choices and trade-offs, there are 3 rules-of-thumb in picking green products:

•  When in doubt, don't change.  

•  When changing, only do so for conclusively better choices.  

•  And in general, buy local where you can clearly define the impacts you are making.

Dr. Jeff Howe

September 2007

To download this commentary, click here (pdf).