HDPE is made from ethylene (a base plastic) using a catalytic process. The high pressures that the material is subjected to gives HDPE a temperature resistance of about 120°C or 248°F, and a tensile strength of 4550 psi, making it weatherproof and highly durable.
Its composition also makes HDPE lumber resistant to rotting, fading, or cracking, which are the tendencies of natural wood. All these maintenance-free properties make durable HDPE lumber ideal for outdoor use, particularly decking. In fact, given its strength and its green qualities, it’s plausible that HDPE and other plastics would replace much of the wood, brick, and stone materials for homes in the future.