Trex. Developed in a licensing agreement with Dri-Deck Enterprises, the RainEscape above-joist deck drainage system creates a dry space beneath a second-floor deck, suitable for lighting, ceiling fan, and finished ceiling installation. RainEscape components shield joists to protect them from water damage and deterioration. The system includes a drainage trough sheet, downspout, and butyl waterproof caulk and tape. Installation requires only a utility knife, staple gun hammer, and caulk gun. 800.289.8739.