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DOWSIL Firestop 400 – White Fire-Rated Silicone Sealant (380ml)

£4.13Incl. VAT

DOWSIL™ Firestop 400 is a premium fire-resistant silicone sealant designed to protect building joints, service penetrations and construction interfaces from...

SKU: 2938863/C06

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    Product Details

    • Description

      DOWSIL™ Firestop 400 is a premium fire-resistant silicone sealant designed to protect building joints, service penetrations and construction interfaces from the spread of fire, smoke and toxic gases. Engineered for professional passive fire protection, this high-performance neutral-cure silicone provides excellent adhesion, long-term flexibility and reliable fire resistance.

      Ideal for both new builds and refurbishment projects, Firestop 400 is suitable for use in expansion joints, curtain walling, internal partitions, pipe penetrations and fire-compartment lines. Once cured, it forms a durable, moisture-resistant seal that continues to flex with joint movement while maintaining critical fire integrity.

      Perfect for contractors, installers, HVAC engineers and fire protection specialists looking for a dependable, trade-approved fire sealant.

    • Benefits

      Fire-rated performance — helps prevent the spread of fire, smoke and heat

      • Neutral-cure silicone suitable for a wide range of substrates
      • Excellent movement capability for dynamic joints
      • High durability and long-term resistance to moisture and weathering
      • Strong adhesion to metal, glass, masonry, concrete, timber and plastics
      • Low shrinkage for a consistent, high-quality finish
      • Easy to apply and tool for clean, professional joints
      • Suitable for internal & external fire-stopping applications

    • How to Apply

      Ensure surfaces are clean, dry, and free from dust, grease or loose material.

      1. Apply masking tape for clean edges if required.
      2. Cut the cartridge nozzle and load Firestop 400 into a suitable silicone gun.
      3. Fill the joint evenly, ensuring full contact on both sides.
      4. Tool the sealant within 5 minutes to ensure a smooth, compact finish.
      5. Allow to fully cure before exposing to fire conditions or movement.

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