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A wrong formula, a bad density figure, a nonsense result, an unclear explanation — all of it matters. Reports are checked by hand and mistakes are fixed at the source. Corrections are published below so you can see what changed.

Last reviewed: 8 November 2026 by Ian Welkins

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Corrections

When a confirmed error is fixed, the correction is listed here with the date, so the site's track record is public.

• 7 November 2026: Density figures unified across every page to the calculators' shared data table; worked examples on the tons and cost pages recomputed; fence-post guidance rebuilt around the calculator's layer model; the privacy page corrected after the move to Cloudflare Pages (host and error-form descriptions).
• 8 November 2026: Compaction and ordering guidance unified site-wide (compacted layers: add 10–15%; loose surface layers: 5–10%); play-area depth figures removed and replaced with a pointer to the CPSC playground safety handbook; the concrete page's ready-mix bag comparison corrected; sourcing and review-date wording aligned across the trust pages.
• 8 November 2026 (later review): Leftover contradictions from the same round cleaned up — the driveway worked example and walkway examples now use the same ordering rule, the accuracy guide's input rule aligned, a garbled sentence on the author page rewritten, and the word "anonymous" removed from the analytics descriptions.
• 8 November 2026 (final audit pass): Last wording fixes from the full-site audit — the About meta description's voice, the crushed page's preset wording, a repeated sentence and the depth answer on the walkway page, the patio base example's ordering uplift, and the privacy page's analytics description.
• 9 November 2026: The patio page's worked example named a #67 base where the page's own layer model (and the paver page's matching example) use crusher run; corrected to a compacted crusher-run base — 2.37 yd³ ≈ 3.8 tons, order 4.2–4.4 tons with the compaction uplift.