Product Code: 39588
High performance acrylic based construction sealant for sealing joints and cracks in fire rated internal walls and floors. In the event of fire Firestem™ Intumescent Mastic provides a barrier to flame and smoke preventing the spread of the fire and toxic gases through building joints. 4 hour fire rating on brick, concrete, steel and vermiculite with a single 12.5mm deep seal.
Water based and easy to apply. Firestem™ Intumescent Mastic forms a flexible seal with good adhesion to most common building materials.
When subjected to heat Firestem™ Intumescent Mastic swells (intumesces) to provide an inert barrier to smoke and flame. The fire resistance achievable with Firestem™ Intumescent Mastic depends upon the joint design, depth of sealant and substrates being sealed.
Firestem™ Intumescent Mastic is tested by Warrington Fire Research Consultants to BS476 part 20 and achieves 4 hours Fire Resistance