Recycled Content of Insulation Case Study

ROXUL commissioned MMM Group Ltd. to perform an analysis of LEED certified projects to determine the effect of insulation recycled content on the achievement of LEED credit MRc4. As of 2015, MMM has certified over 280 LEED projects in Canada and has an extensive database of documentation to draw upon.

Using cost data from actual projects, it was determined that the recycled content of insulation products does not significantly affect the achievement of MRc4.


There are 2 points available under LEED credit MRc4 based on meeting a defined threshold of recycled content, calculated as a percentage of total construction materials cost (e.g. CSI MasterFormat® 1995 Divisions 2 through 10). For LEED v1.0, the thresholds are 7.5% (1 point) and 15% (2 points). For LEED v2.2 and v2009, the thresholds are 10% and 20%.

The parameters of the analysis are as follows:

  • 20 LEED certified projects, each documenting ROXUL insulation under MRc4
  • 19 of the projects earned 2 points under MRc4
  • Building types include: education, healthcare, office, municipal, and MURBs
  • The average materials cost for the projects was $10,195,038
  • The average value of ROXUL insulation product per project was $40,410
  • A comparative analysis was performed using a pre-consumer recycled content of 40% and 75%


The project’s total recycled content changed on average by 0.11% when the recycled content of insulation was changed from 40% to 75%. For example, if a project was reporting a total recycled content of 21.00%, increasing the recycled content to 75% resulted in a total recycled content of 21.11%. There was no correlation between building type and the magnitude of change in total recycled content of projects.

The largest difference in total recycled content was found to be 0.73%; the smallest difference was 0.00% due to the fact that the insulation cost was insignificant relative to the overall materials cost.


In general, the recycled content of insulation does not have a significant impact on a project’s achievement of LEED credit MRc4.

For LEED v4, recycled content contribution is calculated similarly (by percentage of cost), and therefore the impact will be similar.

LEED consultants often use a “first past the post” type of method for documenting recycled content. For example, if they have received enough complete product documentation to attain the required recycled content threshold, they may reduce their efforts in acquiring outstanding documentation. For this reason, if a project was ever within 0.73% of the next MRc4 point threshold, outstanding documentation for additional product(s) would most likely be obtained in order to achieve the threshold.

ROXUL remains committed to providing clear documentation for LEED projects, and we are proud to have our products contribute to the success of many projects as evidenced by the number of requests we receive for documentation.

We encourage you to consider all of our insulation solutions for your project. More information can be found here.