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Editorial standards

How we build every estimate

69 calculators, all of them showing their work. This page documents where the numbers come from, how often we re-check them, what they deliberately exclude, and who is accountable when one of them is wrong.

Reviewed by The CostToUpgrade Estimating Desk Last reviewed

Our process

  1. 1.We write the formula first

    Every calculator starts as a pure function with named inputs and outputs — not a lookup table and not a model. The arithmetic is the same arithmetic an estimator does on a legal pad, which means it can be checked line by line. If we cannot write the formula down in three or four readable steps, the tool does not ship.

  2. 2.Constants come from published standards

    Coverage rates, yields, and conversion factors are taken from manufacturer specifications, model building codes, and long-established trade rules of thumb — a cubic yard is 27 cubic feet, an 80 lb bag of concrete yields about 0.6 cubic feet, a roofing square is 100 square feet. Each constant lives in one place in our source so it can be audited and updated once.

  3. 3.Every tool publishes its own math

    Each calculator page carries a "How it's calculated" block listing the exact equations in order, plus a fully worked example with real numbers. You should never have to trust the output — you should be able to reproduce it.

  4. 4.Regional pricing is indexed, not invented

    For the 24 projects where we publish regional data, we hold a single national baseline per unit and scale it by a relative construction cost index per state, where 1.00 is the national average. We publish the whole table rather than splitting it into one page per state, because a comparison is only useful when you can see the whole set.

  5. 5.Ranges, not false precision

    Regional figures are shown as a ±12% band. That is roughly the gap we expect between a competitive bid and a premium one for identical scope in the same market. A single decimal-precise number would look more authoritative and be less true.

Where our numbers come from

Baselines and sizing guidance are anchored to public, checkable sources. Where a figure is a trade convention rather than a published standard, we say so on the calculator itself instead of dressing it up as data.

Model building codes (the IRC and the NEC) are referenced for sizing and clearance rules where relevant. Codes are adopted, amended, and enforced locally — the version your jurisdiction has adopted is the one that governs your project, not the one we cite.

What our estimates leave out

This list is the difference between a material takeoff and a real project budget. Unless a calculator explicitly asks you for it, assume it is not in the number:

  • Labor, unless a unit is explicitly labeled "installed"
  • Sales tax, delivery fees, and bulk-material minimum-order charges
  • Permits, inspections, and engineering or architectural fees
  • Demolition, disposal, and hauling of the old material
  • Site prep, excavation, grading, and access difficulty
  • Repairs to whatever you find once the old surface comes off

On a labor-heavy job, adding these back can roughly double a material-only figure. That is not a flaw in the estimate — it is why the estimate is a starting point for a conversation with a contractor rather than a replacement for one.

Who maintains this

The CostToUpgrade Estimating Desk

Authors & reviewers

A small editorial team that builds and maintains every calculator on this site. We write the formulas from published construction standards and trade rules of thumb, document the sources on each tool, and re-check unit assumptions and national price baselines on a published schedule.

We deliberately publish under a team name rather than inventing a named expert with a stock headshot. The accountability is real either way, and this way nothing on the page is fictional. If you need to reach the people behind a specific number, contact us and it comes to us directly.

How we make money, and what it doesn't buy

This site is free and carries no paywall, no account, and no gate on any tool. It is funded by display advertising and by affiliate commissions from the Amazon Associates program, where we may earn on qualifying purchases made through links on calculator pages. Those links are labeled and marked rel="sponsored nofollow".

What that money does not buy: placement in a formula, a nudge to a constant, a price baseline, or a decision about which calculators get built. We also do not sell your inputs — calculations run in your browser and the numbers you type are never sent to us.

Methodology FAQ

Who writes and checks these calculators?
The CostToUpgrade Estimating Desk. A small editorial team that builds and maintains every calculator on this site. We write the formulas from published construction standards and trade rules of thumb, document the sources on each tool, and re-check unit assumptions and national price baselines on a published schedule. We are not a contractor, a supplier, or a lead-generation broker, and no vendor pays to influence a formula or a price baseline.
How often are the numbers reviewed?
Formulas and their constants are re-checked whenever a relevant standard changes — those move rarely. National price baselines get a full review on a published schedule; the most recent was August 1, 2026. Every calculator and dataset page shows its own last-reviewed date, so you never have to guess how stale a figure is. Material prices are the fastest-moving input, so anything more than a quarter old should be confirmed against a current supplier quote.
How accurate should I expect these to be?
The quantity math is exact for the inputs you give it — if you enter a 10 × 12 ft slab at 4 inches, the cubic yardage is not an estimate, it is arithmetic. The cost math is only as good as the unit price. Using your own local quote for the price field will typically land you within 10% of a real material invoice. Regional index pricing is looser: treat it as a sanity check on a bid, not as a bid.
Do ads or affiliate links change what you recommend?
No. We run display advertising and we participate in the Amazon Associates program, which means we may earn a commission when you buy a tool through a link on a calculator page. Those links are marked and carry rel="sponsored nofollow". No advertiser or affiliate relationship influences a formula, a constant, a price baseline, or which tools we build. If a product link ever conflicted with giving you the right number, the link would go.
I think one of your numbers is wrong. What do I do?
Tell us, and be specific — the calculator, the inputs you used, the result you got, and the figure you believe is correct with a source. We would rather fix a constant than defend it. Corrections go through the same review as a new tool, and the page's last-reviewed date is updated when a change lands. Use the contact form and we will reply.
Is any of this a substitute for a professional estimate?
No, and it is not meant to be. These tools exist so you walk into a contractor conversation already knowing your quantities and a realistic budget range, which is what lets you compare bids on equal footing. Anything structural, electrical, or code-governed — spans, conductor sizing, equipment sizing, permits — needs a licensed professional and the locally adopted code, and every one of those calculators says so on its own page.