Many reasons. Sometimes the water table is too high. Sometimes the ground isn’t actually colder because it is a material that retains a lot of heat. Digging is expensive. And of course, most people don’t want to live underground.
Digging basements is really expensive!
And comes with a lot of other issues to handle, as you need to ensure proper ventilation, avoid water infiltration, etc.
And making sure that inhabitants can escape in an emergency (egress). That’s doubly difficult if you want more than one level to the house.
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Many reasons. Sometimes the water table is too high. Sometimes the ground isn’t actually colder because it is a material that retains a lot of heat. Digging is expensive. And of course, most people don’t want to live underground.
Digging basements is really expensive!
And comes with a lot of other issues to handle, as you need to ensure proper ventilation, avoid water infiltration, etc.
And making sure that inhabitants can escape in an emergency (egress). That’s doubly difficult if you want more than one level to the house.