The Flintstone House, Experimental residential building in Hillsborough, United States.

The Flintstone House is a free-form single-family residence in Hillsborough, California, built on a concrete slab with shotcrete sprayed over steel rebar and wire mesh on inflated balloons. Its bulbous domes, painted deep orange since 2000, carry round and oval windows with dark frames; two small orange cylindrical vents sit on the roof. Inside are about 2,700 sq ft, three bedrooms and two bathrooms.

Architect William Nicholson designed the house in 1976 for Tyrone and Norma Thompson, one of several experimental domed buildings built by Fame Homes using shotcrete sprayed onto steel rebar and wire mesh over inflated aeronautical balloons, an idea inspired by Wallace Neff's airframe homes. Water runoff from the mountainside cracked the foundation by the mid-1980s, and the house was extensively restored in 1987. Architect Eugene Tsui remodeled it during the 2000s.

The property displays steel dinosaur sculptures and cartoon characters throughout its garden, making it a recognizable landmark for travelers passing by. These playful decorations reflect the owner's creative vision and give the house a distinctive presence in the neighborhood.

The building provides natural insulation that reduces heating and cooling expenses compared to conventional construction. The unusual structure requires careful navigation through curved rooms and rounded corners when moving through the spaces.

The spiral staircase to the third bedroom was modelled on an ice cream cone: at the top it matches the room's diameter. The master bathroom floor is laid with rocks instead of tiles. The house was built by spraying shotcrete over inflated balloons, and its first owner, Norma Thompson, planned to give tours and lectures there.