Editorial, sources, and corrections policy
CountStruction separates calculation evidence from commercial links. A retailer relationship never determines a formula, default allowance, safety note, recommendation, or product quantity.
Calculator content
We favor primary sources: manufacturer technical data, adopted-code text, government safety material, and recognized trade-association guidance. When a value varies by product or site, the input remains editable and the interface labels it as a planning assumption.
Review and change control
Material formula changes require a known-example test and a review of units, boundaries, rounding, result language, and the shopping list. The public review date is updated when that calculation is rechecked; copy-only edits do not imply a new technical review.
Corrections
Calculation defects take priority over new features. A useful report includes the calculator URL, every entered value, the displayed result, the expected result, and the product or technical source used for comparison. Confirmed errors are corrected in the formula, tests, explanation, and affected shopping-list lines together.
Commercial disclosure
Compensated retailer links are marked near the shopping list and use sponsored-link attributes. Prices and availability come from the retailer at click time; the calculator does not claim that a linked product is the cheapest, in stock, or suitable for every assembly.