PURPOSE: To improve the heat resistance, sound insulation, and vibration damping property of wall by making one or both walls, between which sound insulator is placed, from an alloy-base vibration damping steel plate having a predetermined vibration damping loss factor.

CONSTITUTION: A partition wall 20 is formed so that a sound insulator 22 is sandwiched between alloy-base vibration damping steel plate 21 having a vibration damping loss factor η not less than 8×10-3. The vibration damping steel plate 21 may be used for only one of steel plates 21a or 21b. The vibration damping loss factor should be nearly the same as that of a wooden wall to insulate conversation sound. This constitution provides a wall having high heat resistance, sound insulation, and vibration damping property.