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Specialist advice on hand

DOWSIL Firestop 400 - 380ml
(100839)
DOWSIL Firestop 400 is a one-part, intumescent acrylic sealant designed to maintain the fire integrity of fire-rated walls, doors, windows and partition joints. Provided in a 380 ml cartridge, this fire-stop sealant swells under heat to form a fire- and smoke-resistant barrier — helping to prevent passage of fire and smoke for up to 2 hours (depending on joint configuration). It adheres well to many common construction substrates without needing a primer, making it a reliable and easy-to-apply solution for fire protection in internal fire-rated structures. Key Features Fire-rated — can achieve up to 2 hours fire resistance under tested joint conditions One-component, ready-to-use, non-slumping paste — simple application from cartridge Good adhesion to common building substrates without primer Intumescent — swells under heat to seal fire- and smoke-rated joints Joint movement capability: ± 7.5% — allows some structural movement or slight shifts without compromising seal i
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DOWSIL Firestop 400 is a one-part, intumescent acrylic sealant designed to maintain the fire integrity of fire-rated walls, doors, windows and partition joints. Provided in a 380 ml cartridge, this fire-stop sealant swells under heat to form a fire- and smoke-resistant barrier — helping to prevent passage of fire and smoke for up to 2 hours (depending on joint configuration). It adheres well to many common construction substrates without needing a primer, making it a reliable and easy-to-apply solution for fire protection in internal fire-rated structures.
Key Features
Fire-rated — can achieve up to 2 hours fire resistance under tested joint conditions
One-component, ready-to-use, non-slumping paste — simple application from cartridge
Good adhesion to common building substrates without primer
Intumescent — swells under heat to seal fire- and smoke-rated joints
Joint movement capability: ± 7.5% — allows some structural movement or slight shifts without compromising seal i








