This is a standard white foam underlay. 3mm in thickness with an integrated HDPE vapour barrier. Thisunderlay will reduce impact noise by up to 18db. The roll dimensions are 3mm x 1m wide by 15m long.This is not suitable for use with underfloor heating.Integral HDPE layer to help protect against moisture - up to 3% MC12 Micron (approx.) HDPE layer - 200mm joint overlapExcellent impact sound insulation - 18dBAbsorbs minor floor imperfectionsNon-dusting, non-toxic & odourlessSimple, quick & easy to installLightweight and easy to handleCFC & HCFC free100% recyclableSuitable for use over underfloor heatingThermal Resistance (R-Value) - 0.116m?/K/WTog Value - 1.16