Duralay Silentfloor Gold 15sqm Sponge Rubber Wood & Laminate Underlay: 4.2mm Thick, 0.33 Ultra Low Tog, 1.37m x 11.00m Roll Designed for laminate & solid timber floors. Also complements under-floor heating systems, allowing heat to easily pass through. This 4.20mm sponge-rubber flat underlay is engineered for use under laminate or solid-wood floors. The thin waffle also complements under-floor heating well guaranteeing you a delightfully warm feel underfoot, as well as warmer rooms in general. Silentfloor Gold is a premium laminate underlay, with outstanding acoustic properties. Also 4.20mm flat sponge, It comes with a gold Vapourstop membrane, which protects against moisture damage to the flooring from beneath. At 53 sone, the impact sound qualities of this underlay mean that no matter who is pounding across the floor, you will not be deafened.