Terms of use
Last updated 14 August 2026.
Estimates only
The calculators and guides on this site produce planning estimates. They are not engineering advice, a structural design, or a quotation. Real projects vary with site conditions, local code, material availability and workmanship.
Verify every quantity with your supplier and every structural decision with a qualified professional before you order materials or begin work. You are responsible for how you use these figures.
No warranty
The site is provided as is. We work hard to keep formulas and constants accurate and test them automatically, but we make no guarantee that any figure is correct or fit for a particular purpose, and we accept no liability for loss arising from its use.
Content
Site content and code are ours. You are welcome to use the results of a calculation for any purpose, including commercially. You may not republish the content itself at scale without permission.
Changes
We may update these terms as the site develops. The date above shows the current version.