CostPlain pages are written to be accurate, useful and honest about where each number comes from, and about what an estimate cannot know. This page sets out how that works and where its limits are.
How a page is made
- Research. We start from primary sources and from our cost register, and note what they do and do not settle.
- Writing. A draft is written from that research under the CostPlain name.
- Fact-check. A separate check compares each price, wage, fee, date and rule with its source, and reworks every sum on the page.
- Graphics. Any charts or diagrams repeat figures from the text and add no new facts.
- Final review. A last read looks for errors, gaps and unsafe advice. If it finds a serious problem, the page is fixed and reviewed again. We do not publish a page with a serious problem still open.
Each page ends with the date its sources were checked. No process catches everything, so please tell us if you find a mistake.
Our sources
Every wage, fee, permit or code rule, tax rule, standard, safety instruction and date links to a primary source at the claim. We use sources such as the Bureau of Labor Statistics, EIA, ENERGY STAR, the Department of Energy, EPA, CPSC, FEMA, the IRS, state and city agencies, university extension services, and manufacturer specification sheets.
Installed prices are the exception, because most have no primary source. For those we show named published estimates, each dated and labelled with what it measures, next to our own build-up from materials, wages and a stated overhead line. Our how we estimate costs page explains the method. If we cannot confirm something, we leave it out or say plainly that it is unconfirmed.
What we do not claim
- We have no crew and do no jobs. We never say “we tested” or “we got quotes”, and we do not claim to have done the work we describe.
- We do not invent authors, quotes, homeowner stories or contractor comments.
- We do not rank contractors, products or materials unless public data supports the ranking, and we do not call anything “best” on the strength of an opinion.
- We never call a price “fair”, and never call a job “safe”, “up to code” or something “you can do yourself”. We give estimates; a licensed local contractor and the permit office decide.
- Photos are stock images chosen to illustrate a topic. They do not show jobs we have done or homes we have seen.
Safety
CostPlain gives prices, not repair instructions. A price can look like permission, so we follow these rules:
- No do-it-yourself steps for electrical panels, service upgrades or circuits; gas lines and gas appliances; foundations, load-bearing walls or jacking. A licensed contractor and the local building department decide.
- No advice to climb onto a roof to inspect it.
- Pages on gas appliances carry gas-smell and carbon monoxide notes in the words of a federal safety source.
- Pages where paint, siding, windows, drywall or insulation are disturbed carry EPA’s lead paint and vermiculite (asbestos) guidance for older homes.
- Sewage cleanup wording comes only from health or emergency agencies, with a pointer to the local health department.
- Building codes are adopted locally, so we do not state a single national code or permit rule.
Fairness
Contractors’ and sellers’ claims are reported as claims. Many published cost ranges come from sites that sell leads to contractors, and we name the source so you can weigh it. For structural work, we suggest an assessment from someone who is not selling the repair, because a crack alone does not show its cause. Sometimes the honest answer is that a repair can wait, or that a cheaper fix is worth asking about.
Calculators
Our calculators are formulas with named inputs and shown working, and each formula is checked against answers worked by hand before it goes live. Every default that is a price or an hour count says where it comes from, or that it is our assumption, and you can change it. Calculators print numbers only, so read the notes on the page around them.
Updates and corrections
Prices, wages and rules change, so we recheck any figure older than 12 months, and sooner when a source it relies on changes. A page shows an updated date only when its content really changed. Errors are fixed and recorded on our corrections page.
Advertising and independence
Display advertising pays for this site, and advertisers have no say over what we publish. We use no affiliate links, accept no paid placements, sell no leads and make no contractor referrals. Our about page has more on how the site works.