Key takeaways
- Revision four lowered our water factor from 3.4 to 2.7 gal/lb after a customer's consultant supplied better mill data.
- Trees are now applied to the virgin share of the furnish only, not to the whole board weight.
- It is the second revision that has made our own claims smaller, and we publish revisions rather than quietly restating.
- Three things we still leave out: landfill methane, fibre-length value, and reused accessories.
In November a sustainability consultant working for one of our larger accounts sent a polite three-paragraph email explaining that our process-water factor was too high. She was right. Revision four of our factor set, published in January, lowers it from 3.4 to 2.7 gallons per pound of avoided containerboard.
That reduces our headline water claim by about twenty per cent. It is the fourth time we have revised these numbers and the second time a revision has made us look worse.
What changed
| Factor | Was | Now | Reason |
|---|---|---|---|
| Process water avoided | 3.4 gal/lb | 2.7 gal/lb | Better mill recirculation data; older figures predate modern closed-loop systems |
| Trees per ton | Applied to all fibre | Applied to virgin share only | Recovered fibre does not come from trees; applying the conversion to the whole furnish overstated it |
| Carbon intensity | 0.95 lb CO₂e/lb | 0.95 lb CO₂e/lb | Unchanged; still mid-range for North American production |
| Freight netting | Lane-based | Lane-based, backhaul-weighted | Refined to reflect the 38% of miles that run on matched returns |
Why publish the revision rather than just update the number
Because anybody who used our previous figures in a report now needs to know they have changed, and in which direction. Quietly restating is how numbers lose their meaning.
It also, frankly, makes the remaining numbers more credible. A factor set that has only ever moved upward is a marketing document.
The most useful email we received last year told us we were overstating a benefit. We would like more of those.
The revision history, complete
- Revision 1, 2021 — first published factor set. Single carbon figure, no freight penalty, no stated counterfactual. Honest but thin.
- Revision 2, 2023 — freight penalty introduced after an internal review concluded our claims were unqualified. Lowered headline figures by roughly seven per cent.
- Revision 3, 2025 — board weights replaced with our own scale data across a thousand-plus measured boxes, rather than supplier catalogue figures. Raised some figures, lowered others.
- Revision 4, 2026 — water factor reduced; trees applied to virgin share only; freight netting refined.
Where the numbers remain conservative
Three places we deliberately leave value on the table:
- Avoided end-of-life emissions. Landfilled corrugated generates methane as it decomposes; counting it would raise our figures materially, but the rate varies so much by site that we leave it out.
- Fibre-length value. Every pulping cycle shortens fibre and eventually forces virgin input into the system. Reuse defers that permanently and no standard factor set captures it.
- Accessories. Liners, caps, pallets and wrap that also get reused are excluded from headline numbers unless a customer specifically asks for a full-shipment model.
Use them yourself
The factors are published openly and are not proprietary. If your sustainability team wants to apply them to volumes bought elsewhere, that is a perfectly good outcome — better data in the market makes every reuse argument easier to have.
Questions