Recycled Plastic and Composite Lumber for construction in USA

Recycled Plastic and Composite Lumber

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Recycled Plastic and Composite Lumber

Plastic and wood composite lumber are quickly becoming a common replacement for redwood, cedar, and treated lumber in such applications as decking, door and window frames, and exterior moldings. Treated lumber, frequently used for decking, used to be treated with toxic copper chromated arsenic (CCA), which must be disposed of as hazardous waste. While the newer alternate treatments do not contain arsenic, they can leach copper, which is toxic to aquatic life. Redwood and cedar decking use virgin trees, maintaining our dependence on scarce wood resources. Plastic and wood composite lumber are worked similarly to real wood and do not require treatment, yet they hold up well to water, sun, insects, and salt air, typical enemies of wood.

Recycled Plastic and Composite Lumber

Both recycled plastic lumber and recycled wood/ plastic composite lumber are molded or continuously extruded into standard lumber forms. 100% plastic lumber is usually made with 100% recovered plastics such as HDPE, LDPE, PET, or a mixture of various recovered plastics. Check the fine print, though, as today a number of manufacturers produce 100% virgin plastic or PVC lumber. The HDPE raw material comes from post-consumer waste (primarily milk and laundry bottles and plastic bags), LDPE from plastic bags and shrink wrap packaging, and PET from post-consumer soda bottles. Wood/ plastic composite lumber is made from a 50/50 mix of plastic resins (typically trash bags) and reclaimed wood such as sawdust from furniture manufacturing plants. Manufacturers claim that recycled wood/ composite plastic lumber is more rigid than 100% recycled plastic lumber because the wood fibers act as reinforcement. The plastic encapsulates and binds the wood to resist moisture penetration and degradation from fungal rot, bringing together some of the best properties of both wood and plastic.

Plastic lumber is commonly available in three grades: hollow, solid, and structural solid. Hollow grade plastic lumber is used for light-load applications such as low-load deck surfaces, fence signage, and shutters. Regular solid grade plastic lumber is used for medium-to-light load applications, such as deck surfaces and planters. Structural grade plastic lumber has a 20% fill of fiberglass to provide superior strength and reduce expansion and contraction issues.