LEED®-NC 2009 Recycled Content Value of Steel Building Products

The U.S. Green Building Council's Leadership in Energy & Environmental Design (LEED®) Green Building Rating System aims to improve occupant well-being, environmental performance, and economic returns of buildings using established and innovative practices, standards, and technologies.

Materials & Resources Credit 4: Recycled Content intends to increase demand for building products that incorporate recycled content materials, thereby reducing impacts resulting from extraction and processing of virgin materials. As discussed and demonstrated below, North American steel building products contribute positively toward both available points. The following is required by LEED-NC:

Credit 4 (1 or 2 points) "Use materials with recycled content such that the sum of postconsumer recycled content plus one-half of the pre-consumer content constitutes at least 10% or 20% (based on cost) of the total value of the materials in the project."

“The recycled content value of a material assembly shall be determined by weight. The recycled fraction of the assembly is then multiplied by the cost of assembly to determine the recycled content value.” Since steel (the material) and steel (the building product) are the same, the value of the steel building product is directly multiplied by steel’s recycled content, or:

Steel Recycled Content Value = (Value of Steel Product) (Post-Consumer % + ½ Pre-Consumer %)

The information contained within this brochure provides post-consumer and pre-consumer recycled content percentages for North American steel building products and is considered acceptable documentation by the USGBC LEED rating system and green codes and standards. These percentages and values of steel building products are easily entered into the LEED Letter Template spreadsheet for calculation.

To illustrate the application of these steel recycled content values to LEED, manual calculations are shown below for typical Basic Oxygen Furnace (BOF) and Electric Arc Furnace (EAF) steel building products with nominal $10,000 purchases, using 2011 data. Steel building products include steel stud framing, structural steel framing (wide-flange beams, channels, angles, etc.), rebar, roofing, siding, decking, doors and sashes, windows, ductwork, pipe, fixtures, hardware (hinges, handles, braces, screws, and nails), culverts, storm drains, and manhole covers.

BOF Steel Recycled Content Value for Typical Product:
Steel Stud Framing
BOF Steel Recycled Content Value = 19.8% + (½ x 14.4%) = 27%
Value = ($10,000) (27.0%) = $2,700
(Positive net contributor to 10% and 20% minimum percentage for each point threshold)

EAF Steel Recycled Content Value for Typical Product:
Wide-Flange Structural Steel Framing
EAF Steel Recycled Content Value = 69.0% + (½ x 19.5%) = 78.8%
Value = ($10,000) (78.8%) = $7,880
(Positive net contributor to 10% and 20% minimum percentage for each point threshold)