I've thought about different types of houses over the years. I think that the most important thing for the future is that houses be built to last, be low maintenance, cheap to build, and cheap to live in (heat/cool.) Wait, that's four things. OK, well, they are all important. Wolf's comment about living in the ground is the obvious answer to all of these concerns. The problem with living in the ground is that water wants to get in, and there is no light.
One interesting building concept I read about is a
Passive Annual Heat Storage building that absorbs heat in the summer, and uses it in the winter. In theory, such a house would have zero heating and cooling costs, and would maintain a constant temperature year round. Problem is, they don't look too nice to live in. However,
one house in the hills of western Virginia has achieved a nice balance. They use the PAHS idea to reduce the house's seasonal temperature change to only 13 degrees Fahrenheit, without heating or cooling. That's amazing when you consider the summers sometimes get up to 105 degrees, and the winters usually get down to the teens. My own home, which I spend an arm and a leg alternately heating and cooling has an internal temperature swing of about 15 degrees during the year. I just can't afford to moderate it more than that. Besides the energy benefits, the house above actually looks pretty nice to live in. They have plenty of light, with large windows on three sides. The place was built for less than a "normal" house. It's stronger, is more storm resistant, the copper panel exterior is virtually maintenance free, and it's much more energy efficient.
There's a good discussion about it
here . (I think you may need to register, they just recently changed the Taunton webpage.) VaTom is the poster who built the house, and he talks a lot about it in this thread.
Just imagine, a house that stays at room temperature year round for free!