These natural fibre boards are designed to reduce impact sound by up to 18dB when used with laminate and wood flooring, helping to combat noise. Also helping to deal with minor subfloor irregularities, the 5.5mm thick boards are suitable for DIY and should be used on top of Fast-Fit Polythene Damp Proof Membrane or Lumberjack M.B Primer. Each pack covers approximately 7m2.