Materials and Resources - Credit 4

Recycled Content (1-2 points)

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The intent of this credit is to increase demand for building products that incorporate recycled content materials, thereby reducing impacts resulting from extraction and processing of virgin materials. The requirements are to use materials with recycled content such that the sum of post-consumer recycled content plus one-half of the pre-consumer recycled content constitutes at least 10% of the total value of the materials in the project to receive 1 point and 20% to receive 1 additional point. Supplementary cementitious materials, such as fly ash, slag cement and silica fume, are considered pre-consumer recycled content. Furthermore, using recycled concrete as aggregate instead of virgin aggregates would qualify as post-consumer recycled content. Although not considered part of concrete, most reinforcing bars are manufactured from recycled steel and considered post-consumer recycled content.

There are two methods for calculating recycled content.  For example, assuming the following:

 

  • 5,000 yards3
  • 4,000 pounds per yard
  • 600 pounds cementitious
  • 200 pound slag/ash (33%)
  • $100 per yard3
  • $50 cement per yard3

 
Method 1: Based on Concrete (200/4000)*0.5 (pre-consumer recycled content) * 5000 * $100 = $12,500 of recycled content. 

Method 2: Based on Cement (200/600)*0.5 (pre-consumer recycled content) * 5000 * $50 = $41,667 of recycled content.