Underground housing, underground businesses, etc. Would that be better for the environment + possibly save on energy costs? Also possibly safer in certain scenarios like tornadoes etc.
Potential issues that immediately come to mind are ventilation, earthquakes, and flooding. But it’s not like underground dwellings/basements/etc. aren’t a thing, so maybe those issues have been addressed in ways I’m not familiar with.
And what, just break our treaty with the dwarves and end a peace that has lasted a thousand years?? We get the top 10 feet, they get everything deeper. I won’t go to war in the dark over a housing shortage we created ourselves through greed.