There is a logic to a round house, according to their proponents: air flows smoothly around them which makes them safer in storms and easier to heat; they enclose the most volume for a given surface area. Of course the last time I wrote that, the first comment was "This story indicates the need for a new writer and a new editor." Also, much of that efficiency is lost because they are so hard to furnish. In 1959 Juni Ludowici designed and built this Rundhaus, which probably should have been called Kugelhaus since it is not just round, but spherical.
It's a cute little plan, 14'-9" in diameter, 171 square feet at its widest point. I particularly like the delivery system.
Does anyone know if this still exists?