Warmup Insulated Underlay 25m²Warmup® Insulated Underlay is a thin polystyrene insulation barrier with effective acoustic properties to reduce contact noise. It sits between the cold subfloor and foil heater reflecting heat upwards, making the underfloor heating system more efficient and effective. The foil backing acts as an effective moisture barrier. Features: Resists heat loss and increases the efficiency of the underfloor heating system. Extremely effective in reducing contact noise. Very thin at only 6mm in depth. Lightweight and easy to install. Foil backing acts as a moisture barrier. Recommended for use in combination with Warmup® Dual Overlay when installing resiliant floor coverings. Tech Specs: Size: Width – 1200mm Coverage/Pack – 2.5sqm, 5.0sqm, 10sqm, 25sqm Thickness: 6mm Composition: Top Layer: Grooved polystyrene, Bottom layer: Silver foil with adhesive overlap Rm value: 0.19 m2 K/W Contact Sound Reduction: 25dB ?Lw when used in conjunction with Warmup® Dual Overlay