Thermoguard Intumescent Mastic
  • Thermoguard Intumescent Mastic

Thermoguard Intumescent Mastic


Thermoguard Intumescent Mastic is an easy to apply, intumescent sealant that provides a 5 hour fire barrier coupled with excellent sound reduction properties. Permanently flexible and excellent slump resistance it is ideal for sealing gaps around fire doors, window frames and for sealing joints, voids and irregular holes in fire rated structures.

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£3.60 Tax incl.


Thermoguard Intumescent Mastic is a one part, acrylic based intumescent sealant that provides a 5 hour fire barrier coupled with excellent sound reduction properties. It is permanently flexible and can be installed in up to 50mm joints due to it's excellent slump resistance. Formulated to be halogen free it is ideal for sealing gaps around fire doors, window frames and for sealing joints, voids and irregular holes in fire rated structures. The sealant forms a char, preventing the passage of fire and smoke, when exposed to the heat of a fire.


  • Block Wall, Concrete, Masonry and Plasterboard Partitions.
  • Linear Joints up to 50mm wide in concrete floors, masonry walls and plasterboard including head of wall details.
  • Metallic pipes, cable trays, cable bunches, small, medium and large cables.

Thermoguard Intumescent Mastic has been independently tested in accordance with BS476 and EN requirements. It can provide up to 300 mins of fire resistance depending on depth/width and volumetric area - please refer to the Performance Table.

It has good unprimed adhesion to a wide variety of common building substrates. although we do recommend that a small area is tested on unusual substrates.

IMPORTANT FIRE PRODUCTS NOTICE: The information displayed on this website should be used as a guide ONLY and our Technical Department should be contacted to obtain a tailored specification and any advice necessary before you place an order for fire protection products. Fire protection products are non-returnable except in accordance with Condition 8 of the Terms and ConditionsWe will not be held liable for any resulting damage to property, human life or monetary costs incurred due to the incorrect specification you have prepared or use of fire protection products caused by your negligence, including your failure to have contacted us to obtain the relevant advice/specification.

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