For projects pursuing LEED certification, the question of the impact of any material on the Recycled Content and Regional Content credits consistently arise. This is understandable. During the design of a project it is difficult to tell what products will ultimately come from within the requisite 500 mile radius or what their recycled content will be. If a project wants to insure that it will achieve these LEED credits, it makes sense to insist from every vendor that their products be regionally sourced and that they have recycled content. Unfortunately, sustainability is not a black and white issue and these credits can sometimes conflict. In other words, material within the 500 mile radius may not have the highest recycled content available. Additionally, manufacturers beyond the 500 mile radius may offer other benefits that can save costs or speed construction or meet a design requirement that addresses other sustainability goals.
Designers who select materials solely on the basis of meeting these two LEED criteria may be missing other opportunities for creative expression or sustainability. So, how does one know when to broaden the criteria for material selection? We have decided to take a look at several LEED certified projects to assess the relative contribution of certain materials or specified items to the Material & Resource credits for Recycled Content and Regional Materials. Since this site is focusing on brick, we will begin here but, we plan to be able to provide metrics for other materials so stay tuned.
We have compiled data from several LEED projects built with brick exteriors. Comprised of a variety of building types, all projects are located in the Baltimore, MD/Washington, DC metro region.
Recycled Content
In the sample we have compiled, total recycled content represents between 18% and 55% of the cost of the materials (divisions 2-10) of the project. Though some brick contained recycled content, others did not. For the sake of this exercise, we calculated the impact for both zero and one hundred percent recycled content to illustrate what the potential material impact would be. In fact, few bricks will include one hundred percent recycled content. The impact of 100% recycled brick on the total recycled content of a project varied between 2.26% and 3%. This is the total potential contribution of brick to this credit. In most cases, because few brick are made of 100% recycled content, it will be lower than this. Fifty percent recycled content in brick for the represented projects would yield an impact of 1.13% to 1.5%, for example.
As previously mentioned, the total recycled content of these projects varied from 18%-55%. Projects whose recycled content exceeded twenty percent meet the LEED requirement for achieving the two points available under this credit. Many projects received the Innovation in Design Credit for Exemplary Performance by meeting or exceeding thirty percent recycled content for the materials on the project. Whether or not the brick contained recycled content was insignificant to the achievement of the maximum number of points for this credit.
Regional Materials
Using the same sample of buildings, the total value of materials regionally sourced ranged from 9.17% to 50.3% of total material costs (divisions 2-10). Again we calculated each project at zero and one hundred percent of the value of the brick for this credit. Again, the contribution of brick to the total value of regionally source materials was between 2.26% and 3% overall.
In the case of the Regional Material credit, the sample of projects revealed that many of the projects in the Baltimore/Washington area were obtaining more than thirty percent (30%) of their materials regionally, well above the twenty percent (20%) required to achieve the two available points under this credit and enough to achieve the Exemplary Performance point under Innovation in Design. In this case, the contribution of brick to the achievement of this credit could be the difference between qualifying for the Innovation point or not but, for all projects, it did not impact the project’s ability to qualify for the two points available under this credit.
Regional Materials
Using the same sample of buildings, the total value of materials regionally sourced ranged from 9.17% to 50.3% of total material costs (divisions 2-10). Again we calculated each project at zero and one hundred percent of the value of the brick for this credit. Again, the contribution of brick to the total value of regionally source materials was between 2.26% and 3% overall.
In the case of the Regional Material credit, the sample of projects revealed that many of the projects in the Baltimore/Washington area were obtaining more than thirty percent (30%) of their materials regionally, well above the twenty percent (20%) required to achieve the two available points under this credit and enough to achieve the Exemplary Performance point under Innovation in Design. In this case, the contribution of brick to the achievement of this credit could be the difference between qualifying for the Innovation point or not but, for all projects, it did not impact the project’s ability to qualify for the two points available under this credit.
Sustainability
It is true that whether one achieves a LEED point or not, the embodied energy, and therefore the embodied carbon, of a material is likely to be greater if one has to transport it farther – particularly if it is a heavy material like brick. But, if one wants to truly drill down to this level of detail, one would have to consider such things as the efficiency of the plant where the material is manufactured, where the raw material is harvested, whether the brick will be transported to the local distributor by truck or rail as well as the relative impact of any potential increase in embodied energy to the total life-cycle benefit of building a brick building. While I would support such an exercise, I do not anticipate that it will be part of a typical design process.
This exercise is intended to assist design teams in evaluating the relative contribution of their material decisions on these particular LEED credits and to place these decisions in the context of the overall project sustainability goals. As this author has frequently expressed, sustainability is about so much more than LEED. Each project needs to be considered in its entirety as well as for its individual credit compliance.
It is true that whether one achieves a LEED point or not, the embodied energy, and therefore the embodied carbon, of a material is likely to be greater if one has to transport it farther – particularly if it is a heavy material like brick. But, if one wants to truly drill down to this level of detail, one would have to consider such things as the efficiency of the plant where the material is manufactured, where the raw material is harvested, whether the brick will be transported to the local distributor by truck or rail as well as the relative impact of any potential increase in embodied energy to the total life-cycle benefit of building a brick building. While I would support such an exercise, I do not anticipate that it will be part of a typical design process.
This exercise is intended to assist design teams in evaluating the relative contribution of their material decisions on these particular LEED credits and to place these decisions in the context of the overall project sustainability goals. As this author has frequently expressed, sustainability is about so much more than LEED. Each project needs to be considered in its entirety as well as for its individual credit compliance.
In summary, designers should focus on the big picture and the strategies that contribute to a project’s overall sustainability. Yes, one needs to be conscientious about material selections but, most non-structural material selections are likely to have small to insignificant impacts on the overall compliance with the Recycled Content and Regionally Sourced material credits. Consider your location, what other materials are contributing toward targeted credit compliance and the projected value of the material in question. What are the other considerations; aesthetics, a manufacturer’s ability to meet fabrication and schedule requirements or cost. Discuss your options with your LEED consultant.
For a full report, contact Potomac Valley Brick at info@PVBrick.com.
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