Plastic lumber, even though it doesn’t need to be kiln dried or planed, is sold with the same finished dimensions as wood lumber because these dimensions have become an industry standard. A plastic lumber 2×4 is actually 1.5 inches x 3.5 inches… just like a 2×4 made of natural wood.

Made from fiberglass reinforced recycled high-density polyethylene (HDPE) plastic, structural grade plastic lumber is a great alternative to treated wood. It is made with plastic that typically comes from milk jugs and detergent bottles and is an ideal material to use for all types of heavy commercial infrastructure projects.