Parallam Plus PSL (parallel strand lumber) from iLevel by Weyerhaeuser has Wolmanized preservative protection, offering strength and consistency in exterior applications. The improved preservative treatment is compatible with galvanized fasteners and penetrates to the product’s core to protect against termites, fungus, and groundwater contact. Parallam Plus PSL columns and posts can be installed in the ground and can tolerate exposure to saltwater. Available in headers, beams, columns, and posts (and suitable for decking supports, carports, and retaining walls), it can be painted or stained with an oil-based finish. It is made with veneer strips bonded together in a press and microwave process.