5mm Sonic Gold is an underlay for use on all wood and laminate flooring. Featuring a gold foil backing for added insulation and water resistance. This underlay has the capabilities to accommodate minor subfloor imperfections and is produced using closed-cell polyethene foam featuring an integrated gold foil moisture barrier. It is the perfect underlay for reducing impact and airborne noise, making your floor quieter with 25dB reduction. Requirements: Barrier Pro X Tape is required to join the seams on this underlay. Available here at B&Q