Rockwool LRB Slab

Rockwool LRB slab is a light resin-bonded, semi-rigid rock wool board used for insulation at up to 400-450°C. Its lower density makes it lighter and flexible enough to bend around curved surfaces, so it is used for light-duty pipe and duct lagging and other semi-rigid applications.

Rockwool LRB slab is rated up to 400-450°C. Its lower density of 48 or 64 kg/m³ gives less resistance to heat than the denser RB grades, so for surfaces above this range Rockwool RB Slab or Rockwool LRB Roll, both rated up to 650°C, are the usual choices.

LRB slab is a semi-rigid 48 or 64 kg/m³ board rated up to 400-450°C; RB slab is a rigid 96 to 144 kg/m³ board rated up to 650°C; LRB roll is a mesh-faced wired mattress of 64 to 128 kg/m³ rated up to 650°C depending on density. LRB slab suits lighter, lower-temperature lagging, RB slab suits rigid hot surfaces, and the roll suits large or irregular equipment.

LRB slab is supplied in 1000 mm x 600 mm pieces, 25, 40, 50, 75 or 100 mm thick, at 48 or 64 kg/m³. The 64 kg/m³ grade is the firmer option for higher temperatures within its range, while 48 kg/m³ is lighter and easier to shape. It is available unfaced or foil-faced.

Rockwool LRB slab has a thermal conductivity of 0.035 to 0.042 W/mK at 50°C mean temperature. It is non-combustible, Class A1 to EN 13501-1, has water absorption below 2% by volume and a chloride content below 10 ppm.

Yes, LRB slab is semi-rigid and flexible enough to follow curved surfaces such as ducts and larger pipes. It is usually secured with wire or Insulation Band & Buckles and then clad; on smaller pipes, Rockwool Pipe Section gives a neater fit. Foil-faced slab joints can be sealed with Aluminum Foil Tape.

Outdoors, LRB slab needs a weatherproof cladding such as Aluminum Cladding Sheet & Coil, fixed with Self-Tapping Screw fasteners and with overlaps sealed using Silicone Sealant. Mineral wool that stays wet loses much of its insulating value, so cladding joints should shed water and be maintained.

Rockwool LRB slab is supplied to ASTM C612 and IS 8183, with a Class A1 non-combustible fire rating under EN 13501-1. If your specification requires specific test reports or third-party inspection, mention it in your enquiry and we will confirm what can be arranged for the order.

Rockwool LRB slab is exported under HS code 6806 90 00, the heading for mixtures and articles of heat-insulating mineral materials. It is packed in poly-wrapped bundles on pallets and can be combined with pipe sections, cladding and bands in one FCL or LCL shipment. Verify the national tariff line with your customs broker.