I spent New Years Eve with a family from my church yesterday.
In the lounge they had under-floor heating. It was lovely and warm.
If I had not taken my shoes off at the door, I am sure my feet would have been drenched in sweat.
Under-floor heating is quite common in shoe-removing South Korea.
I am sure under-floor heating is expensive, but it does go really well with having a shoes-off policy.