WiseWrap® JoistTape™ is a malleable polyethylene waterproof wood flashing tape utilizing a rubberized asphalt mastic adhesive. When applied to the top of deck joists it creates a waterproof seal that helps stop decay and wood rot. It self-seals around fastener screws blocking the primary pathway for water infiltration into deck joists. Likewise, it helps with noise reduction of squeaky deck boards. Place between ACQ, CA-B, or ACZA treated lumber and metal surfaces to create a physical barrier. This prevents the corrosion of the metal surface caused by contact with the chemicals in treated lumber.