Abstract: Glass fibre reinforced plasterboard including a gypsum matrix of high density with embedded staple glass fibres therewith forming a pressure resistant solid body frame in which are embedded a plurality of very small hollow spaces of 5-350 microns in diameter, produced by a fine-pore foam or at least partially by small particles of non-porous and non-water absorbing fillers. During the manufacturing process of such glass fibre reinforced gypsum board, the gypsum and the fibre pieces are given only so much water that the water/gypsum ratio does not exceed 0.6, whereafter a foam and/or pourable or free-flowing fillers are added in such quantities that the apparent density of the entire board is at least 20% smaller than the density of the bonding means component of the matrix, and the paste is subjected while being formed to a vibration.