Abstract: A building comprising strong thermal insulation, at least some walls of which consist of panels made of a low-density thermally insulating material, wherein the panels have edge surfaces which are uniformly planar over an entire thickness thereof and are assembled to one another by interleaving boards in joint areas between two adjacent panels, the boards being connected in contact with the panels over an entire length and width of edge surfaces in said joint areas, so that a junction of the boards with the panels prevents by itself alone deformation of the boards in bending transversally to their plane and in twisting and that the panels ensure wind bracing of the walls.