This & That, Ceci et Cela

Domes save energy because there is less surface area per square foot to heat or cool compared to the square or rectangular home. It also allows wind to blow around it rather than into it. Variations: geodesic domes & monolithic domes. Geodesic domes, sold mostly in kit form, are formed by joining pyramid-shaped tetrahedrons together. These dome are usually framed in wood and the outside is covered by shingles or cedar shakes. Most companies who sell kits offer a basic package containing directions and material to frame the dome. Some offer triangle and pentagon windows, roof shingles and interior drywall or wood panelling for an extra cost.

Geodesic drawbacks: It’s difficult to shingle and the triangle studs that form the inside walls make dry walling a nightmare. Possibility of leaking.

Monolithic domes are domes are very energy efficient -especially in high heat areas. Also good for areas like Tropical Islands where hurricanes etc. cannot destroy them.  They’re built in a very unusual way. After a concrete ring foundation is poured, a heavy vinyl Airform is manufactured to the shape and size of home requested. The Airform is spread out and fastened to the foundation. Large blower fans inflate the Airform and remain on during the construction process. Everything else is done from inside. The doors and windows are framed in. Then several layers of polyurethane foam are sprayed on the interior surface of the Airform until there is approximately 3 inches. Steel reinforcing rebar is attached to the foam followed by three inches of Shotcrete, a special spray mix of concrete. The Shotcrete can be smoothed out or left as is for a textured effect and is usually spray painted white. Other than that, the interior wall is complete. The vinyl Airform is the only covering needed on the outside and will last 10 to 15 years before it needs to be painted or stuccoed. Because the rigid foam insulation is on the outside (protected by the vinyl) and the concrete is on the inside, the dome acts as a heat sink, storing heat in the winter and keeping it out in the summer. Expect lower cooling/air conditioning bills but a bit higher heating bill.  More here at the official monolithic dome site.
Monolithic drawbacks: some users encounter heat loss through windows in winter, but remedied by covering them with foam panels at night. Leaking windows a possibility. So do plan well & pay utmost attention to window detail especially if living in places with winters. That +slightly higher heating bills make it better suited to warmer climates.
Dome Examples: