Rebecca Weitzel and Jeff Waschkowski live in a buried home in Omaha, Nebraska and while winters temperatures can hit negative 30 degrees (record lows), inside the home is affected by the temperature of the earth, not the air, and mostly fluctuates between 64 and 74°F.
Do you have any problem with frost heaves?
The only part of the house subject to frost upheaval would be the exposed entrance wall, and the should be protected from upheaval as would any such wall.
Another great video by Kirsten Dirksen. This video does a good job of showing how underground/earth sheltered homes can be extremely energy efficient. It’s nearly a zero energy home. However, the building method was very costly and energy intensive. We recommend using more sustainable building methods such as earthbag building. Every building method is different and you have to learn to work within the constraints of that material. For instance, you could not build the same shape of domes in this home with earthbags.
Here is an alternative, lower cost solution: Artvark by Sustainable Design Projects in Portugal: https://naturalbuildingblog.siterubix.com/earthbag-earthship-design-portugal/
This design could be altered to create a home similar to the one in Omaha.