Add the following new Further Explanation section, after "Creating the Baseline Building":
"Small Scale Reuse
The reuse of building materials can be accounted for in Option 4 - Whole Building Life Cycle Assessment. Typically, projects pursuing large-scale reuse of buildings and materials may pursue other options in this credit - most of which offer more points than Option 4. However, small-scale reuse of materials can be accounted for in this credit along with the project team’s other strategies to reduce the life cycle impacts of the building materials. Essentially, the reuse of building materials removes the initial “one time” raw resource extraction and manufacturing stages (A1-A3) from the Proposed building’s impact.

The majority of available LCA material or whole building tools do not directly support the modeling of salvaged materials. Therefore, project teams should follow the following steps to account for small-scale material reuse in whole building LCA modeling.

1. Model all materials as “new” in the Baseline building
2. Model all materials as “new” in the Proposed building along with other materials impact reduction strategies being pursued for this credit.
3. Determine the amount of salvaged material that will be used on the project. Be sure to account for losses that tend to occur in repurposing products for a new building. For instance, if one can expect a 5% loss in materials in order to repurpose them, the material quantity used in the next step should only be 95% of what is installed in the building.
4. Using the same LCA tool as above, model only the reused materials for the proposed building and save the environmental impact results from stages of raw material extraction, transportation, and manufacturing (A1-A3) impacts only.. Generate and save this information as a separate model file if the tool requires one to do so.
5. Subtract the results of Step 4 from Step 2 to obtain a final result for the proposed building."