In one embodiment, a multiwall sheet can comprise: a first wall; a second wall; an intermediate wall disposed between the first wall and the second wall; a first set of ribs disposed between the first wall and the intermediate wall; a second set of ribs disposed between the second wall and the intermediate wall; a cavity disposed between adjacent ribs; wherein the multiwall sheet is configured to expand and/or collapse when a mechanical force (preferably shear force) is applied to the intermediate wall. Preferably the multiwall sheet has a flexural rigidity of greater than or equal to 10 N/mm.