Patent ID: 8889248

Claim:
A multiwall sheet comprising: a first wall; a second wall; an intermediate wall disposed between the first wall and the second wall; ribs disposed between the first wall and the intermediate wall and between the second wall and the intermediate wall, wherein at least one of the ribs forms a riser having a height as measured between one wall and an adjacent wall; a base having a length which extends from one end of the riser across the adjacent wall to a location where a next rib that extends away from the one wall meets the base, and wherein the height of the riser is less than or equal to 50 percent of the length of the base; wherein no ribs are in direct vertical alignment so as to align from the first wall to the second wall, and wherein there are no ribs on a side of the first wall opposite the intermediate wall or on a side of the second wall opposite the intermediate wall; and wherein the multiwall sheet comprises a polymeric material.