The Rockwool RW5 50mm acoustic insulation slab is a premium-density stone wool product, engineered for high-spec acoustic, thermal and fire applications. Each slab measures 1,200 mm × 600 mm and the pack covers approximately 2.88 m² (4 slabs).
With a nominal density of 100 kg/m³, this slab offers excellent mass and acoustic absorbency — making it ideal for separating walls, ceilings, floors or environments where noise reduction and fire safety are critical.
Its thermal conductivity is rated at 0.034 W/m·K (λD), so alongside acoustic benefits you’re getting solid thermal insulation performance too.
Crucially, the RW5 slab is classified Euroclass A1 (non-combustible) under BS EN 13501-1, meaning it won’t burn and is suited for fire-sensitive builds.
The semi-rigid stone wool format allows for easy handling and friction-fit installation between studs, joists or rafters — helping you maintain full cavity fill and reduce gaps that compromise performance. The high density resists sagging or deformation over time, offering long-term reliability.
Installation tip: Ensure slabs are cut to size, fit snugly edge-to-edge with no voids, and the surrounding structure is sealed (especially around services and penetrations) to optimise acoustic and fire performance.
Whether you’re specifying for high-traffic commercial partitions, multi-residential flats, sound-sensitive spaces (like home cinemas or offices) or any refurbishment where depth is limited but performance counts — Rockwool RW5 50 mm gives you a trusted, spec-ready solution.

Key Features

• Thickness: 50 mm — deeper than thinner options for better acoustic/thermal balance.

• Dimensions: 1,200mm × 600mm (L×W).

• Pack coverage: ~2.88 m² (4 slabs per pack).

• Density: 100 kg/m³ — high mass for superior sound dampening.

• Thermal conductivity: 0.034 W/m·K — strong thermal insulation.

• Fire rating: Euroclass A1 (non-combustible) — top fire safety.

• Material: Stone wool (rock mineral wool) — naturally fire-resistant, dimensionally stable, water-repellent.

• Applications: Internal partitions, separating walls/floors/ceilings, media rooms, commercial and residential refurb.

• Installation: Semi-rigid slabs, cut to fit, friction-fit between studs/joists, minimal gaps.

Technical Specifications