In a Korean home the floor is the radiator. Warm water runs through pipes under the surface, and the heat rises through the whole room instead of pooling near a wall.
It changes the furniture
If the warmest place is the floor, you sit on the floor. Low tables, thin mattresses that get folded away, cushions instead of armchairs. Even in flats full of sofas, people end up on the rug.
It changes the shoes
Nothing worn outside touches a surface people sit on. This is why shoes come off at the door, and why the entry is a step lower than the rest of the flat.
Staying somewhere with ondol
Set it low and leave it. Ondol takes an hour to warm a room and holds the heat for hours after. Turning it up and down all evening only makes the floor uncomfortable.
Sample article for layout review. Final content to be written.