Editorial policy
Our guides and blog posts exist to help you buy the right amount of material and do the job once. This page explains how they're put together. For the math behind the calculators, see how we calculate.
Where the numbers come from
Every number in an article comes from a named source or from math we show on the page. The sources are the people who make or regulate the thing: manufacturer data sheets, building codes, industry groups like the American Concrete Institute, and university extension services. We name them in the text, not only in a list at the bottom, so you can check any figure yourself.
When sources disagree, we say so and show both. When we couldn't find a published number, we tell you that instead of guessing.
What we won't do
- Invent quotes, reviews, customer stories or personal experiences.
- Rewrite a press release or a news item and call it an article. A post has to add something: a worked example, a table, a check of other sources or our own calculation.
- Write about things our calculators don't cover just to chase traffic.
Dates
Each article shows the date it was published. If we change the substance of a piece, like a new code requirement or a corrected number, the date changes and the page says "updated". We don't change dates to make old pages look new.
Photos and diagrams
Diagrams and charts are our own, drawn from the numbers in the article. Photos come from free sources such as Wikimedia Commons, with the photographer and license credited under each one.
Independence, ads and affiliate links
ShedMath isn't owned by or paid by any manufacturer, retailer or contractor. No one pays to be mentioned in an article, and we don't accept guest posts or paid links.
We may show ads, and some links may earn us a commission in the future. If a link earns money, it's labeled on the page and marked as sponsored for search engines. Ads never sit on top of a calculator or its result.
Corrections
If you spot a mistake, email [email protected] or use the contact page. We check the claim against the source, fix it if it's wrong, and mark the article as updated.
Who's responsible
Emre Özen runs ShedMath and is responsible for everything published here. More on the about page.