It provides the perfect level of support and protects your floor from excess wear. Comfort Silver has a built in DPM vapour barrier with an overlapping 150mm edge. It can be used on concrete or wooden based sub floors and removes the unevenness. One side laminated with metalized silver vapour barrier preventing any moisture rising. The closed cell polyethylene foam is 100% recyclable, and so kinder to the environment. The Roll size is 15m x 1m with a thickness of 3mm and a Comfort Rating 3* Vapour tape (Not Included) is required to fix the seams of the underlay which also provides a fully secure Damp Proof Membrane.