FS4 Fireshield AC Intumescent Acrylic Sealant

FS4 Fireshield AC Intumescent Acrylic Sealant

FIRESHIELD AC is a high performance intumescent sealant, flexible acrylic sealant and adhesive which, in the event of a fire will swell to provide a smoke resistant barrier.


Product Code MS01B

966 in stock

Next day delivery available


FIRESHIELD AC is specially manufactured to form an acoustic and fire rated intumescent barrier in construction applications. When subjected to heat Bond It FIRESHIELD AC swells (intumesces) to provide an inert barrier to smoke and flame. The fire resistance achievable with Bond It FIRESHIELD AC depends upon the joint design, depth of sealant and substrates being sealed. See detail overleaf.

It is non-slumping and rapid skinning. It can also be overpainted within 1 hour.

This sealant has been tested to the following Specifications:

  • BS EN 1366-3: 2004 & BS EN 1366-4: 2006 achieving 4 hour integrity and insulation rating for a range of linear and penetration seals.
  • BS EN ISO 10140-2:2010. Measurement of Airborne Sound Insulation of Building elements. The sealant maintained the integrity of a plasterboard partition wall with a Sound Reduction Index of 55dB.


  • Solvent-free
  • Permanently flexible
  • Non-shrinking
  • Conforms to EN-1366-3, EN-1366-4, EN ISO 10140-2: 2010