Examples of pre-consumer recycled content exclusions

Hi Michelle,Valid pre-consumer content includes aluminum scraps from a curtainwall manufacturer, sent back to a smelter to make new aluminum, or waste wood fiber from a sawmill used to make MDF. Classic examples of internally reused scrap that does NOT qualify as pre-consumer recycled content are:

• steel manufacturering scraps generated within a steel mill and remelted to make new steel within that same mill (as opposed to scraps generated at a factory that makes steel studs, sent back to the steel mill--those WOULD qualify);
• float glass (used to make windows) that comes off the end of a line off-spec or otherwise imperfect, and is remelted in that factory to make new glass.

If you're a BuildingGreen Suite member or subscriber to Environmental Building News you can find a lot more details on this in the article "Recycled Content:
What is it and What is it Worth?"

Nadav, I recently received the following comment on a LEED Review: It is noted that template lists a product that contains float glass and it is unclear whether the claimed recycled content percentage includes cullet material. Please note that the reuse of cullet does not meet the LEED definition of pre-consumer material, and it must not be considered recycled content in the credit calculations. For future projects, please ensure that all cullet material has been excluded from the pre-consumer recycled content of all float glass materials. I don't understand why anything with cullet would be excluded, as the definition of cullet is: crushed glass for re-melt in furnace. Could be from glass containers, light bulbs etc. My understanding has always been that cullet was a result of glass container recycling operations. I could see it being considered post consumer, but don't understand why it is being excluded all together.

If I were to interpret this, I think they are intending to say to exclude it from pre-consumer calculations, not all together, especially since their last comment says "For future projects, please ensure that all cullet material has been excluded from the pre-consumer recycled content of all float glass materials." It would be worth emailing the reviewer to clarify.

I'm thinking that a call to the float glass people would be better. They should have more information/control over their manufacturing process and should know if their cullet is all internal process cullet or has external cullet (from consumer recycling). What is less clear to me is the use of cullet from one glass making process to another glass making line. For example, if I'm making clear float glass for a week and at the end of each day I put the waste glass materials back in the furnace to make more float glass that is an internal process. But what happens the next week when I switch from making clear float glass to making colored float glass and use some of the waste clear cullet from the week prior? Pre-consumer or internal process?

Cullet is notorious for being counted as pre-consumer recycled content by manufacturers, when all they are doing is taking waste glass from the end of their line and putting it back in at the beginning. The reviewer is probably being attuned to this. Perhaps overly so, but I agree, the manufacturer should be able to provide more information.