Hey I was surprised not to see a post here on this topic yet, so let me introduce:
REScheck
This is a tool produced and maintained by the US Department of Energy that allows you to take a building and calculate it's performance criteria to prove compliance.
We use it as an alternative path to meeting code when deviating from a standard building assembly.
You don't need to be an architect to use it, and it is totally free, but you do need to have some idea of the U/R values of the materials you are using, and the qualities of the windows and doors you're installing.
Thankfully, all this information has been largely studied, so whether you are building with strawbales, hempcrete, cob, or any of the other earth-based techniques, there are published tested values for all of these things.
(Volhard, Kirick, Minke, and Birkhäuser publishing for established values - Sunbeam books is a great source if you're in the USA)
https://www.energycodes.gov/rescheck
This is where you start.
There are published guides on how to use it.
If you get stuck, post questions below and I'll answer them if I can.