GOAL: a wall that loses less thermal energy through diffusion, can transport moisture outwards and meets or exceeds requirements for statics, fire prevention and acoustic.
Important to understand: U-Value (the inverse of the American R-Value):
The lower the U-Value of your building envelope is, the better it is able to insulate you from fluctuations in outdoor climate. With a better-insulating envelope, considerations have to be made to keep air quality high, which is where ventilation and air quality come in.
One of the most common errors in building envelope planning is building moisture. When moisture isn't considered during the planning (or worse, construction) of a building, the ramifications can be career-ending. Growing up during the "Leaky Condo Crisis" of the 90s made for a constant reminder of the consequences of ignoring regional climate, combined with poor material choice and excessive moisture not able to escape a building's envelope. It boils down to this: in our climate, the moisture that forms through predictable building physics must be able to diffuse quickly and uninhibited towards the outside of the envelope. Everything else plays second fiddle.
Local fire codes will dictate which materials you may or may not use, depending on the type of project you have planned. It behoves you to understand at the very least how each material utilized will react in a fire situation.