TimberTech2 Silver Plus 3mm Underlay has a built in silver foil moisture membrane (dpm) which prevents moisture rising from the subfloor. This makes it perfect for the installation of laminate and wood floors on concrete or wood subfloors. At 3mm thick it can level out subfloor imperfections and has an excellent 21dB of sound reduction. TimberTech2 Silver Plus 3mm underlay can be used with underfloor heating. The low tog rating of 0.37 allows the room to heat more efficiently. *Suitable for underfloor heating. We do not recommend an underlay is used with an electric mat (or dry) underfloor heating system.