E04C2/00—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels
E04C2/30—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure
E04C2/40—Building elements of relatively thin form for the construction of parts of buildings, e.g. sheet materials, slabs, or panels characterised by the shape or structure composed of a number of smaller components rigidly or movably connected together, e.g. interlocking, hingedly connected of particular shape, e.g. not rectangular of variable shape or size, e.g. flexible or telescopic panels