MR C5 Regional Materials Multiple components

Brooke—In the MRc5 chapter of the LEED 2009 BD+C Reference Guide, Table 2 shows a “Sample Assembly Percentage Regionally Extracted Calculation for Concrete” as an example of how to calculate regional content in a product with multiple components. To make this calculation, you do need a breakdown (by weight) of the product’s components and data indentifying the extraction sites for as many of the components as possible. For concrete, you may not even realize that you have access to the required information. Structural engineers usually require concrete suppliers to submit “mix design” reports for each type of concrete used on a project. These “recipes” show the proportions of each component in each mix, usually in pounds per cubic yard. These reports should also identify the quarries that produced the aggregates, the plants that produced the fly ash, and the manufacturers that made the cement and admixtures. I usually calculate material percentages for both MRC4 & MRc5 using these reports. Be aware, though, that a single project typically uses many different types of concrete, each one with a different “recipe” comprising different proportions of ingredients. I would expect suppliers to submit a different “mix design” and report a separate cost for each type delivered to the jobsite.

The answer depends on which version of the MR calculator you are using. A new version just came out on January 4, 2016, but you may be using an older version. If you are using the previous spreadsheet (which I think was dated Aug 2012), and if you are using Option 1, go to Cell P7, and select “Option 1.” Now, in Column O of the line where you have entered the cost of the concrete mix, enter the Regional Percentage (in your case, 92.6%). In Column Q, enter the distance to the farthest regional extraction point (less than 500 miles). Do not average. In Column R, enter the “Manufacture Distance” (the concrete mix plant). This approach works unless you are using the SCM Alternative approach for MRc4. In this case, you should have separate costs for cementitious and non-cementitious materials, so you enter the values for each mix on two separate lines and calculate the regional content separately for each. If you are using the new MR calculator (labeled “v06”), see the instructions in the discussion just below this one: http://www.leeduser.com/comment/redirect/62554.

Brooke - You were correct! See http://www.leeduser.com/comment/redirect/67712 below.