That's pretty much standard in interior Alaska now. That gives an R-30 rating for insulating value. R-40 plus for ceilings.
My sister and her husband retired in northern Arkansas. They built like it was Alaska, and people thought they were nuts. Their summer AC bills sure are impressive, though.
If you do build a super insulated house, you need to install an air to air heat exchanger or you will not get CO2 buildup inside your house
Super insulated is R sixty or better. Typically you need to spray foam to achieve these levels. In these type of houses your only heat loss is through your Windows and exterior doors.
I meant you will get CO2 buildup in the house.
The problem with most houses, even New ones, is they are not built to be passive solar. They do not have deep enough overhangs on the south and west side of the house to block the sun coming in during the summer. These overhangs would allow the sun to come on in during the winter when the sun is lower on the horizon. Passive solar also requires more thought out window orientation. Up here in New England that means you do not put big picture Windows on the north or east side of the house. This is why almost ALL ski areas in New England face north or east. If they face south or west the snow MELTS and runs down the hill.
My daughter’s house has an airlock between the main entrance door and the house. I mean it has a little mud room with a tile floor about 6x6. It has another exterior insulated door between it and the house. It has lockers built into one wall to store your coats, gloves, hats,etc. The other wall has a double shelf for boots and assorted footwear. That wall is lined with hooks for coats.