Abstract: The present invention is related to a method for manufacturing a substantially planar and horizontal rigid structure constituted by building elements which are jointed to each other, comprising the steps of successively moulding said building elements from a rapidly polymerizing foamed plastic material; transferring successively said building elements, immediately after polymerization of said plastic material to a predetermined location in the structure to be obtained, so as place each one of said elements into a juxtaposition with respect to the previously transferred element, said transferring step being carried out preferably after a modification of at least a portion of the surface of said elements; and jointing to said predetermined location to the element which has previously been transferred.