Fireproof building element

Fire proof building element with a multi-sheet glazing unit of glass or glass ceramic characterized in that at least one of the glass sheets of the multi-sheet glazing unit is a fire resistant glass sheet and that the building element contains at least one high heat reflective layer or contains one or more high heat reflective foils arranged between the sheets at a distance from the fire resistant glazing unit, characterized in that the fire resistant glazing unit consists of glass sheets whose product of the thermal expansion unit .alpha. (20.degree.-300.degree. C.) and elasticity module E is between 1 and 5 (kg/cm.sup.2 .multidot..degree.C.) and which are put into the area of the frame by partial hardening under a compressive stress characterized in that the sheet away from the fire is thicker than the sheet toward the fire and the distance between the sheets is between 2 mm and 150 mm, also characterized in that the glass sheets consist of a glass that shows a strong curve at the upper surface crystallization, and characterized in that the glass sheets in the area of the frame of the sheet or on the total upper surface possess a crystalline upper surface with a lower thermal expansion value than the value of the base glass, the building element being filled with a gas which has a thermal conductivity less than the thermal conductivity of air, and also characterized in that the high heat reflective foils are made of aluminum or gold which reflect over 90% of the radiation, and also characterized in that the high heat reflective foil is put in a rolled up form or in a folded form between the two sheets of the building element such that the visible area is not covered and which can, in the event of a fire, be spread out completely between the sheets.