Sources and evidence standards
A citation must support the specific claim beside it. A familiar publisher or a long source list cannot establish that a statement applies to your roof.
What each kind of source can establish
- Adopted requirements: name the jurisdiction, issuing authority, edition, amendments, effective date, and verification date. A model-code passage alone does not establish the rule at a property.
- Product instructions and tested assemblies: name the product or assembly, document revision, test or approval, and the conditions of use. Do not transfer a result to another assembly.
- Measured evidence: describe the study population, method, climate, sample limits, and date. An observation is not a guaranteed outcome.
- Costs and service life: distinguish quotes, reported observations, planning assumptions, and warranties. Publish scope, units, geography, date, and exclusions with any number.
- General education: identify assumptions and explain where an on-site assessment or local authority must settle the question.
What to look for in a source card
Look for the source title, publisher, direct link, the claim it supports, and important limits. An edition or date matters when the facts can change. An access date means a source was accessed; it is not an expert-review date.
Review intervals
Recheck costs and changing local or product facts when updating a guide. Stable geometry needs less frequent attention. A correction, recall, revised instruction, changed local rule, or credible conflicting source can trigger an earlier update.
Disagreement and AI assistance
When credible sources disagree, explain the conditions behind the difference. Narrow or omit an unsupported claim, or seek specialist input for the unresolved question. AI tools have assisted development and drafting; generated text, images, and citations are not independent evidence.