Product description

It’s perhaps even more essential to have advanced fire protection in underground services and penetrations than it is in over ground construction given the high risk of exit in the event of a fire. ROCKWOOL LUL Intumescent Sealant has been specially developed to offer a versatile and durable solution to providing firestopping around service penetrations within underground applications. 


This water-based sealant contains an acrylic emulsion which makes it appropriate to seal various underground joints that may pose a fire risk. Suitable for sealing a wide range of materials, ROCKWOOL LUL Intumescent Sealant can be used to treat the joints in masonry walls, steel to masonry, softwood to masonry, timber to masonry, as well as plasterboard. To add extra peace of mind, this product is best used in conjunction with any ROCKWOOL LUL approved slab. Part of the ROCKWOOL FIREPRO© range, this sealant ensures maximum protection should there be a fire, where it will expand and block any crevices in the joints to stop the passage of smoke and fire.



ROCKWOOL LUL Intumescent Sealant fully complies to BS476: Part 20 (1987) regulations.

LUL Approved

IFC Certified

  • Maximum protection – ROCKWOOL LUL Intumescent Sealant offers 2 hours of fire resistance, creating a lasting fire protection.
  • Permanent service utility – this product can be used to protect non-combustible steel pipes of up to 60mm wide, and multicables with diameters up to 15mm.
  • Zero maintenance – requires no ancillaries, which makes it a cost-effective solution to fire prevention.
  • Versatility – suitable to use to seal various fire rated walls and door frames, including those made from masonry, steel, softwood, timber and plasterboard.