Doyle, Scribner and International Log Rules — Validation Note
Understand why named log-rule estimates differ and why Scribner remains held.
Three names do not mean three conversions
Doyle, Scribner and International ¼-inch are distinct yield-estimation systems. They apply assumptions about how a log may become lumber and can produce materially different BF estimates for the same recorded diameter and length. Presenting them as interchangeable conversions would be misleading.
BoardFoot Bench releases only the specifically validated Doyle and International ¼-inch table models. The generic Scribner mode remains held because the exact variant has not yet met the evidence standard.
A like-for-like example
At 16 inches small-end diameter inside bark and 16 feet, the retained Doyle cell is 144 BF and the International ¼-inch cell is 180 BF. The 36 BF difference is a model difference, not a measurement error. A user should not average the values or choose the higher number without a governing rule.
Sources of divergence
Historical kerf allowances, slab deductions, taper treatment, diameter response and rounding contribute to differences. Actual mill recovery introduces further variation through defects, sweep, sawing pattern, equipment and product mix. No rule result is a guarantee of saleable output.
How to make a defensible comparison
Hold diameter convention, length and deduction constant. Record each exact variant and source table, show gross values before deductions, and explain which rule controls the transaction. Do not include a held Scribner number until its publication and checks are resolved.
Questions about this topic
Which rule gives the highest number?
It varies by dimensions; choosing by outcome is not a valid transaction method.
Can I average rule values?
No. The rules are separate models, not repeated measurements.
Why show a held page?
It documents the boundary and prevents a silent substitute.
Related BoardFoot Bench pages
Method and content reviewed 3 September 2026. This route is excluded from the public sitemap while staging or held.