Bond It FS4 Fireshield AC is a high-performance, flexible acrylic intumescent acoustic sealant. In the event of a fire, it swells (intumesces) to form an inert barrier that prevents the passage of smoke and flames through joints and gaps in fire-rated construction elements.

It is specifically designed to provide both fire-rated and acoustic sealing in construction applications, including floor and ceiling joints, dry lining systems, partition walls, plasterboard installations, and suspended ceilings. It is also suitable for penetration seals around steel and copper pipes passing through plasterboard.

Fireshield AC achieves up to a 4-hour fire rating (dependent on joint design, sealant depth, and substrates) and has been tested to EN1366-3, EN1366-4, and EN ISO 10140-2:2010. It maintains a Sound Reduction Index of 55dB in tested plasterboard partitions. The sealant is solvent-free, non-hazardous, non-shrinking, rapid drying, and can be overpainted within 1 hour.

Key Features:

• Intumescent: swells in fire to block smoke and flames
• Up to 4-hour fire rating (dependent on application)
• Acoustic sealing with 55dB Sound Reduction Index
• Solvent-free and non-hazardous
• Overpaintable within 1 hour
• Permanently flexible and non-shrinking
• Conforms to EN1366-3, EN1366-4, EN ISO 10140-2:2010
• 310ml cartridge