category are parallel strand lumber (PSL) and laminated strand lumber (LSL). All members of this category are strong and predictable, and are thus interchangeable for some applications. PSL is made from veneers that are cut up into long strands and oriented parallel to its length before being compressed into its final shape. LSL is also made from strands rather than veneer, although the strands are shorter and aligned with less precision than PSL and is created as billets that are like a thick version of oriented strand board. Billets of PSL and LVL are very similar although their sizes are different. Billets of PSL can be as large as wide and long while LVL can range up to wide and long. See also Cross-laminated timber Homasote Papercrete Parallel strand lumber References External links "Deck Collapse Conclusions" Plywood Engineered wood Composite materials