PURPOSE: To reduce the cost by constituting a domed house main body section and a leg section supporting the bottom face of the house main body section at the preset height from the ground with a ladder section and a terrace section.

CONSTITUTION: An opening/closing section 6f opening or closing a ceiling and an opening/closing section 6s opening or closing a roof are provided on the roof section 2r of a house main body section 2 formed with multiple flat plate sections 20P... into a polyhedron. A leg section 3 is constituted of legs 3a, 3b, 3c flaringly arranged with lower sides, it supports the bottom face 2d of the main body section 2, and the center of the bottom face 2d is relatively movably connected to the upper face of a base plate 15 via a rotary shaft 16. Multiple flat plate sections 20P... are combined around the main body section 2 to provide a terrace section 5, and a ladder section 4 is fitted at the entrance of the main body section 2. A foundation portion supporting the leg section 3 is formed, the leg section 3 is installed, and members are combined to assemble a built-up house 1. The space of the installation place is saved, and the cost can be reduced.