Terms of Use

Every calculator, chart and guide on the site is free and works without an account. Calculations run in your browser, and the measurements you type are not sent to us. The site is paid for by Google AdSense advertising and by Amazon affiliate commissions, both explained in our privacy policy, cookie policy and affiliate disclosure.

You may use the results for personal and commercial projects, link to any page, and quote individual results. You may not scrape, mirror or republish the calculators, data files or written content in bulk without written permission.

Results are planning estimates. Coverage depends on the product you buy, and the bag or box chart for that product always wins over our numbers. Local energy code, fire code and ventilation requirements take precedence over anything on this site. Read the disclaimer before ordering material from one of our figures.

Everything here is provided as is. We fix errors when they are reported, but we make no guarantee that a result is accurate for your specific building, climate or code jurisdiction, or suitable for any particular purpose.

To the extent the law allows, DixonAppStudio LLC is not liable for material shortfalls, overbuying, construction defects, code violations or any other loss arising from use of the site, from being unable to use it, or from any result it produces.

Some pages link to products on Amazon and to other websites. Prices, availability and the purchase itself are governed by the retailer, not by us, and we are not responsible for the content of sites we link to.

The text, calculators, charts, design and code of the site belong to DixonAppStudio LLC. Product and brand names belong to their respective owners and are used only to identify them.

We may update these terms or any calculator formula at any time; the version on this page is the current one. Questions about these terms go to support@dixonappstudio.com or through the contact page.