There's no contact form here, and no tracking on it. Every page on this site says the maths runs in your browser and nothing you type leaves your device — putting a third-party form handler on the contact page would make that untrue. So it's just an address.
This is the one we most want to hear from you about. Every coverage figure, bag yield and density on this site is published with its source, precisely so it can be checked. If your product's data sheet says something different from ours, theirs is right for your product — and we would rather correct ours than keep publishing a figure that sends someone home short.
enable JavaScript to see this address
Useful to include: the material, the figure we show, the figure your supplier gives, and where it came from.
Questions, a calculator you'd like us to build, something that's broken, or anything commercial.
The addresses above are assembled by your browser rather than written into the page, which keeps them out of the reach of most address harvesters. If you have JavaScript turned off, they'll appear as placeholder text — apologies, and the site's calculators need JavaScript too.
A note on why there's no form. Contact forms are convenient, but they route what you write through somebody else's server and usually carry a tracking script. On a site whose whole argument is that it collects nothing, that would be a small hypocrisy. An email address is older, plainer and entirely under your control — you can see exactly what you're sending and to whom.