Rockwool RWA45 Acoustic Insulation Slab: a robust 3-in-1 thermal, acoustic and fire insulant. ROCKWOOL RWA45 100MM ACOUSTIC SOUND THERMAL INSULATION. Users of RWA45 can rest assured that these premium-quality semi-rigid slabs are not only optimising the fire protection of their build but (with a thermal conductivity of 0.035 W/mK) are also working in tandem to protect its thermal envelope.
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