My house (ranch) is built entirely over a basement except for an 8x8 part of
the kitchen which serves as the dining area. That section is built over what
I'll call a crawl space, although only a cat could crawl into it. Its only
openings are to the basement through two "slots" in the cinder block, each
about the height of a shoe box and twice as long. The house is one of 20
similar ones in the neighborhood, built in the 1950s, and I suspect the
builder offered a few options for saving money.

Anyway, the floor's pretty chilly. I could toss a rug in there, and since
it's not actually in the cooking area, I'd be OK with that. But, I'm open to
other thoughts. The flooring in the entire kitchen needs replacement, and
I've seen a few people here mention heated floors. Is that insanely
expensive? Does it require tile or stone, as opposed to the usual "soft"
flooring materials?