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Flash Harry

FLASH HARRY Bitumen Mastic Trowelable Waterproofing Sealer 1 Litre

FLASH HARRY Bitumen Mastic Trowelable Waterproofing Sealer 1 Litre

Regular price R 170.00
Regular price Sale price R 170.00
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Introducing Bitumen Mastic, your reliable solution for roofing defects and repairs. This heavy-duty, trowel-applied compound is designed to tackle a variety of issues, ensuring your roof stays secure and protected.


  • Versatile Sealing: Seal most roofing defects including roof screw bolts, nail holes, sheeting laps, valleys, gutters, downpipes, cracked tiles, and more.
  • Built-in Membrane: With its built-in membrane, Bitumen Mastic eliminates the need for an additional membrane, simplifying your repair process.
  • Solvent-Based: Ideal for urgent repair work, Bitumen Mastic is solvent-based, ensuring effectiveness even when rain is imminent.
  • Not Suitable for Drinking Water Applications: Due to its solvent-based composition, Bitumen Mastic is not recommended for fish ponds or any drinking water applications.
  • Not Recommended for Negative Water Pressure: While highly effective for most roofing defects, Bitumen Mastic is not suitable for areas exposed to negative water pressure.
  • Flammable Precautions: Exercise caution as Bitumen Mastic is flammable when wet. Take necessary fire precautions during application and storage.
  • UV Protection: In areas exposed to UV, it is recommended to overcoat Bitumen Mastic with Alu-Coat Silver (bituminous aluminium paint) for enhanced protection.
  • Easy Cleanup: Clean up after application with thinners, solvent, or petrol for convenience.

Ensure the longevity and reliability of your roof with Bitumen Mastic. Whether you're facing minor leaks or significant defects, trust Bitumen Mastic to provide a durable, effective solution

What's in the box:

1 x FLASH HARRY Bitumen Mastic Trowelable Waterproofing Sealer 1 Litre

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