How we work

housecosting exists to save you a second trip to the store: measurements in, the amount to buy out, and a cost you can follow line by line.

The math comes first

Each calculator runs on one shared set of formulas. Before a tool is published, its worked example is checked against a calculation done by hand, and an automated test repeats those checks every time the site is rebuilt. The typical values behind the formulas are listed with their references on our method page.

The text around the tools

Explanations are drafted with the help of AI writing tools and are limited to the figures our own calculators and the public data sets on the sources page produce. A writing tool is never the source of a number.

Checks before and after publishing

Scripts test every page before it goes live: working links, readable layout on phones, no thin or duplicated pages. Each week someone on our team reads a sample of the newest pages and corrects what is wrong, and those findings shape the next pages.

Telling us about a mistake

If a result looks off, send the page address and the numbers you entered through the contact page. Confirmed errors are fixed and the review date on the page changes.

Things we will not do

No made-up reviews, no invented experts or quotes, no prices copied from stores, and no selling your request to contractors.