Abstract: A building element 20 comprises a double-skinned panel main member 22, and an elongate fixing member 24 therefor projecting therefrom with a distal shoulder 26 facing the main member 22, the fixing member 24 being provided with anchorage means 24,40,42 passing completely through a block 64 at the edge of the main member 22. The element 20 may be in the form of a kit of parts including holding means 40,42 and spacing means 44. Preferably, element 20 has holes 80 for fixing members 24 of a contiguous element, retained by members 36 inserted through slots 88 and bearing against inner face 84 of block 64.The fixing members as pins 24 may extend perpendicular to edge 56 for corner fixing together of contiguous elements. Pins 24 may be retained at inner face 70 of block 62 by similar means or by threaded means. Pins 24 may be replaced by depending rods 122 bent to provide shoulders 126 in an anchorage trench 128 in flooring base 134.