[QUOTE=enipla]
We would need either completely different building practices, or new and better insulation.
A standard 2x6 wall can take 5-1/2 inches of fiberglass insulation. R-19. You can’t just stuff more insulation in there (compressing it) and get better insulating performance. In fact, it becomes worse.
[/QUOTE]
Well, yeah, but 5 1/2" of pink foam board insulation is R-40 or so.