The LEED Rating System has been a great stepping stone for the building industry to move towards “sustainability”. Within the past few years the USGBC has witnessed the largest growth in its organization and membership. Like some critics say the USGBC may have been in the right place at the right time. It is fair to say however that the use of USGBC standards has helped the industry and the building market move towards more environmentally friendly design and construction, and it deserves better days yet.
The major question is “what is missing in LEED?” Fortunately the USGBC has created chapter organizations in different states and is seeking “regional credit” comments from them in the direction of improving their standards. It is a great idea to have some flexibility in different regions according to resources, climate changes, historical content, etc. But is the LEED Rating System missing major items on the national level? Let us look at the following possible credit additions to LEED:
Life Cycle Assessment
Durability: How could we be “sustainable” and not consider the life a building? Is it the same if a building lasts 30 years versus 100 years? In building A with three times longer life the consumed “material and labor” and the “waste generated” need to be divided by three and then compared to building B with 1/3 of the life expectency. Therefore when we factor “durability” out of a “green standard” we are comparing “apples” to “oranges”.
Repair and Maintenance: Is it “sustainable” if we have an exterior building material that requires painting every five to ten years and yet it only lasts 30 years? Would it not be more “sustainable” if we have a building exterior that lasts over 100 years without the need for any major repair and/or maintenance?
Passive Heating, Cooling, and Lighting: Every design professional would agree that building orientation and location of windows could help reduce the energy consumption of a building by up to 30% and yet this factor is not considered in LEED. There are other passive strategies such as the use of natural ventilation, evaporative cooling, microclimate improvements, radiant heating, etc. It would be logical to add credits step-wise according to the percentage of energy savings due to passive heating, cooling and lighting.
Embodied Energy and Embodied Water: There are materials such as metal that take a great volume of resource to produce. In “aluminum” for instance about 12% of the extracted ore results into building material and the rest goes to landfill. The energy it takes to extract metals out of the ore is very high as well. It therefore makes it very energy intensive to use metal as a building material. In recycling steel not only high levels of energy is required, but also most steel is shipped to China to be recycled. It takes energy to transfer steel waste to China and to bring the steel building product back to the US. This energy use makes “steel recycling” questionable.
Most “rapidly renewable materials” such as “bamboo flooring” are also far transported material coming from Oriental Countries. In the case of “rapidly grown timber” there is a good volume of “embodied water” and “embodied energy” to produce the wood. Non-existence of the embodied energy and embodied water calculation has resulted in our shallow judgment for choosing “sustainable building materials” in some cases.
Retiring Carbon Credits
The building owner today sells his alternative energy credit to utility companies to get some rebates. The utility companies use the consumers’ carbon credits to burn more polluting coal which is a cheaper fuel for energy production. In other words utility companies need to keep their pollution cap fixed and when they buy people’s renewable energy credits they can burn more coal and keep the same cap. The consumer’s effort to use clean energy is therefore offset by more profit for the electric companies. To help really clean the air the USGBC can add “carbon credit retirement” as a condition for the owner to obtain LEED alternative energy credits.
The major question is “what is missing in LEED?” Fortunately the USGBC has created chapter organizations in different states and is seeking “regional credit” comments from them in the direction of improving their standards. It is a great idea to have some flexibility in different regions according to resources, climate changes, historical content, etc. But is the LEED Rating System missing major items on the national level? Let us look at the following possible credit additions to LEED:
Life Cycle Assessment
Durability: How could we be “sustainable” and not consider the life a building? Is it the same if a building lasts 30 years versus 100 years? In building A with three times longer life the consumed “material and labor” and the “waste generated” need to be divided by three and then compared to building B with 1/3 of the life expectency. Therefore when we factor “durability” out of a “green standard” we are comparing “apples” to “oranges”.
Repair and Maintenance: Is it “sustainable” if we have an exterior building material that requires painting every five to ten years and yet it only lasts 30 years? Would it not be more “sustainable” if we have a building exterior that lasts over 100 years without the need for any major repair and/or maintenance?
Passive Heating, Cooling, and Lighting: Every design professional would agree that building orientation and location of windows could help reduce the energy consumption of a building by up to 30% and yet this factor is not considered in LEED. There are other passive strategies such as the use of natural ventilation, evaporative cooling, microclimate improvements, radiant heating, etc. It would be logical to add credits step-wise according to the percentage of energy savings due to passive heating, cooling and lighting.
Embodied Energy and Embodied Water: There are materials such as metal that take a great volume of resource to produce. In “aluminum” for instance about 12% of the extracted ore results into building material and the rest goes to landfill. The energy it takes to extract metals out of the ore is very high as well. It therefore makes it very energy intensive to use metal as a building material. In recycling steel not only high levels of energy is required, but also most steel is shipped to China to be recycled. It takes energy to transfer steel waste to China and to bring the steel building product back to the US. This energy use makes “steel recycling” questionable.
Most “rapidly renewable materials” such as “bamboo flooring” are also far transported material coming from Oriental Countries. In the case of “rapidly grown timber” there is a good volume of “embodied water” and “embodied energy” to produce the wood. Non-existence of the embodied energy and embodied water calculation has resulted in our shallow judgment for choosing “sustainable building materials” in some cases.
Retiring Carbon Credits
The building owner today sells his alternative energy credit to utility companies to get some rebates. The utility companies use the consumers’ carbon credits to burn more polluting coal which is a cheaper fuel for energy production. In other words utility companies need to keep their pollution cap fixed and when they buy people’s renewable energy credits they can burn more coal and keep the same cap. The consumer’s effort to use clean energy is therefore offset by more profit for the electric companies. To help really clean the air the USGBC can add “carbon credit retirement” as a condition for the owner to obtain LEED alternative energy credits.
Social Equity Credits
Since a “sustainable” project needs to be economically, environmentally and socially feasible it would be nice to add some LEED credits for “social equity”. If a project owner or contractor is ready to favor women, minority, and small businesses they could be encouraged by getting some positive credits. If they offer health insurance to the construction workers, or buy building materials from plants that offer group health insurance to their employees they should be able to earn credits. We could also give credits to the owners that are ready to donate building materials or cash to good causes such as “Habitat for Humanity”. These and other social credits could be a driving force towards creating a better society.
Let us hope that we can all contribute to a “greener” livable world where our children will feel safe.
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