WPC Co-Extrusion Decking 150 x 25 mm (4.73 kg/m) is the largest section in our dense co-extrusion range and the best of the range at spanning. With a 150 mm face and 25 mm thickness behind a dense formula (1.261 g/cm3), the section delivers a second moment of area of roughly 195,000 mm4 - about 2.1 times that of the 140 x 20 mm dense board and 1.38 times the 140 x 23 mm. And its weather resistance is not a coating on the surface - it is the section itself: the shell wraps continuously around the profile and is extruded in step with the core as a single body, so there is no facing to peel and no seam to leak. For long spans, less framing and lasting weather resistance in a solid co-extrusion board, the 150 x 25 mm is the top of the range.