Firewise | Acoustic Intumescent Mastic
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Firewise intumescent mastic is a halogen free, polymer emulsion based sealant that swells when subjected to temperatures in excess of 125C forming a char coat that restricts the passage of smoke and fire. It is easily applied and dries to a flexible and smooth surfaced material which is readily over paintable. It has excellent adhesion to a wide range of substrates and will not harden or crack with age.
The intumescent mastic forms a fire and smoke seal in joints up to 35mm wide without slumping. It is ideal for sealing joints in and around internal partitions, lap joints in fire-rated cladding and for sealing between fire doors and fire rated walls. It is recommended that a sealant depth of at least 15mm be applied. If the sealant is to be overpainted, building regulations may require a fire resistant coating.
To achieve a high quality joint, clean all surfaces, remove dust and ensure surfaces are dry. Non porous surfaces should be degreased using a suitable degreasing agent. Highly porous surfaces should be sealed with a suitable primer. Apply masking tape to each side of the joint and gun sealant firmly into the joint, smoothing off with a wetted spatula. Masking tape should be removed within 10 minutes of applications.
The intumescent sealant is not suitable in joints where movements exceed plus or minus 15% of joint width, or in external joints. One tube is sufficient to produce approx. 4m using a 12mm x 6mm bead. Available in: 310ml tubes, 25 tubes per box and supplied in either white, brown or grey.
Firewise intumescent mastic has been independently tested to the following assessments:
BS EN 1366-3: 2004 & BS EN 1366-4: 2006 tested at Bodycote Warrington Fire, report No. 173658A achieving a 4 hour integrity and insulation rating for a range of linear and penetration seals. An indicative fire test based on BS 476 Part 20 at Warrington Fire Research and achieved a 4 hour fire rating (integrity) for a range of vertical and horizontal joints up to 35mm wide between various non-combustible construction materials. A 1 hour fire rating (integrity) was achieved for a range of vertical joints up to 25mm wide between combustible materials (timber).
Naval Engineering standard test NES 711, issue 3 and achieved an average toxicity index of 0.44.
The product provides an ideal intumescent acoustic mastic, as it has been sound tested for acoustic performance values and achieved values of between 46 and 55 dBA indiciating the sealant should uphold acoustic performance requirements of most normal partitioning systems.
The fireproof mastic has also been tested by Warrington Fire for the requirements of London Underground specification LUL1042 for toxicity smoke emission and oxygen index. The results are below the limit required by London Underground Ltd.
Use Case: Fire, Smoke, Acoustic
Applications: Doors & Walls
Test Certification: Fire Tested to BS EN 1366-3: 2004, BS EN 1366-4: 2006 & BS 476 Part 20
Fire Rating: 4 Hours
Acoustic Rating: 46-55 dBA
Material: Halogen Free Polymer Emulsion Based Sealant
Finish: White, Brown, Grey
Fixing: Gun Applied
Included: 1x Firewise Acoustic Intumescent Mastic
Size ml: 310ml