PURPOSE: To hold a building in a floating state by installing a magnetic substance to a slide beam on the bottom of a building in such an orientation that it may repel a magnetic pole of the magnetic substance installed to a foundation surface.

CONSTITUTION: A plurality of magnetic substances 2 are installed to a slide beam fixed with the bottom of a building while magnetic substances 12 having a magnetic pole which repels the magnetic pole of the magnetic substances 2 are installed to a foundation area of a ground G which is opposed to the building. The repelling forces of each of the magnetic substances 2 and 12 are used to hold the building in a floating state. Both ends of the slide beam 1 are freely fitted in a hole 11 bored on a surrounding wall while the regulation of the horizontal movement of the building is carried out by magnetic substances installed to the surrounding wall 10 and the wall surface of the building T. As described above, the building 7 is floatingly held with the repelling force of the magnetic substances 2, 12 and 13 within the surrounding wall 10 at a distance separated from the ground surface G and the surrounding wall 10 in conformity with the repelling magnetic force. Even when the ground surface G is shaken with the vibration of the earthquake, no seismic vibration will be transmitted to the building directly.