Plastic Lumber Disadvantages
One of the primary disadvantages of plastic lumber is its reaction to the thermal environment. The plastic product has an increased rate of thermal expansion and contraction when compared to traditional wood.[ii] Do to this thermal property, plastic lumber is rarely recommended for interior residential projects. Plastic lumber is not as strong as traditional wood, and special care must be taken when handling it on a construction site. Plastic lumber also has a relatively low stiffness and flexural strength. This could explain why plastic lumber is often used for decks or walking surfaces where flexibility is not as important.[i] One rare known safety concern associated with plastic lumber is its resistance to water when burning. If plastic lumber catches on fire, water will only cause the fire to spread. Carbon dioxide, dry chemicals, or foam must be used to extinguish the fire.[iii]
In an effort to help decrease the rising rates of deforestation, alternatives to traditional wood products have been on the rise. When proper precautious and planning is taken, plastic lumber can be an economically and environmentally friendly alternative to traditional wood lumber. With increased understanding of the product and and its performance abilities through standard tests, plastic lumber may see an increased level of usage in the construction industry.