Editorial Policy

One model, published

All cost content is generated from a single model whose formula, inputs and limits are published on the Methodology page. Guides are written to explain that model and standard roofing practice, not to sell products.

Provenance

Every dataset record carries a source and a checked-on date; the build fails without them. Sources are public bodies (the Bureau of Labor Statistics) or clearly-labelled compiled benchmarks. Figures we cannot source, we do not publish — including city permit fees and city-level wages, which do not exist in clean public form.

Independence

No contractor, manufacturer or marketplace pays for placement, estimates or rankings. Advertising and affiliate links are disclosed and never alter a figure.

Maintenance and corrections

Data is refreshed when its sources release (BLS updates each spring) and re-checked at least annually. Verified errors are corrected in the data, which corrects every page the figure appears on, and notable corrections are noted on the Methodology page.