The Rockwool RW5 75mm Acoustic Insulation Slab set on a 43.2 m² pallet is a premium stone-wool slab tailored for high performance in acoustic, thermal and fire applications. With a thickness of 75 mm, the slab provides substantial build-up depth to maximise sound reduction and heat retention, while still being installable in many cavity situations. Standard board size is 1 200 mm × 600 mm, making it compatible with UK studwork, ceiling joists and floor cavities.

This RW5 range boasts a thermal conductivity of 0.034 W/m·K (λD) — meaning this slab plays a solid part in thermal efficiency strategies. It also carries the highest fire-safety classification of Euroclass A1 (non-combustible), meaning the product will not contribute to fire growth, supporting compliance with UK and Irish Building Regulations.

From an acoustic perspective, the RW5 is engineered for challenging sound separation tasks: whether in partition walls, separating floors, ceilings or high-spec renovation projects, the added thickness enhances airborne sound insulation and helps reduce reverberation and noise transfer. Its semi-rigid stone wool construction ensures a secure friction fit between studs, joists or rafters, minimizing gaps that can compromise acoustic integrity. The material is water-repellent, dimensionally stable and designed for long-term performance.

Thanks to the pallet format (43.2 m² coverage), this product is ideal for large-scale installations and trade buyers — perfect for lining entire floors/ceilings or large partition runs where acoustics, thermals and fire safety all matter. The trusted brand and spec-backed performance mean you can confidently pitch it to trade customers or list it on your ecommerce site as a top-tier solution.

Key Features

• Thickness: 75 mm — allows deeper cavity fill and increased acoustic/thermal performance

• Dimensions: Approx 1 200mm × 600mm board size

• Coverage: ~43.2 m² per pallet (trade bulk quantity)

• Thermal conductivity: 0.034 W/m·K (λD) — efficient thermal insulation

• Fire classification: Euroclass A1 (non-combustible) — highest safety rating

• Material: High-density stone wool (rock mineral wool) — robust, non-hygroscopic, dimensionally stable

• Application range: Internal walls, ceilings, floor systems, separating structures, retrofit & new build

• Installation: Semi-rigid slabs that can be trimmed and friction-fitted between studs, joists or rafters; fewer voids = better performance

• Long-term reliability: Maintains thickness & shape, resists sagging or settlement over time